Cybercriminals are abusing a widespread lack of authentication in the customer service platform Zendesk to flood targeted email inboxes with menacing messages that come from hundreds of Zendesk corporate customers simultaneously.

Zendesk is an automated help desk service designed to make it simple for people to contact companies for customer support issues. Earlier this week, KrebsOnSecurity started receiving thousands of ticket creation notification messages through Zendesk in rapid succession, each bearing the name of different Zendesk customers, such as CapCom, CompTIA, Discord, GMAC, NordVPN, The Washington Post, and Tinder.

The abusive missives sent via Zendesk’s platform can include any subject line chosen by the abusers. In my case, the messages variously warned about a supposed law enforcement investigation involving KrebsOnSecurity.com, or else contained personal insults.

Moreover, the automated messages that are sent out from this type of abuse all come from customer domain names — not from Zendesk. In the example below, replying to any of the junk customer support responses from The Washington Post’s Zendesk installation shows the reply-to address is help@washpost.com.

One of dozens of messages sent to me this week by The Washington Post.

Notified about the mass abuse of their platform, Zendesk said the emails were ticket creation notifications from customer accounts that configured their Zendesk instance to allow anyone to submit support requests — including anonymous users.

“These types of support tickets can be part of a customer’s workflow, where a prior verification is not required to allow them to engage and make use of the Support capabilities,” said Carolyn Camoens, communications director at Zendesk. “Although we recommend our customers to permit only verified users to submit tickets, some Zendesk customers prefer to use an anonymous environment to allow for tickets to be created due to various business reasons.”

Camoens said requests that can be submitted in an anonymous manner can also make use of an email address of the submitter’s choice.

“However, this method can also be used for spam requests to be created on behalf of third party email addresses,” Camoens said. “If an account has enabled the auto-responder trigger based on ticket creation, then this allows for the ticket notification email to be sent from our customer’s accounts to these third parties. The notification will also include the Subject added by the creator of these tickets.”

Zendesk claims it uses rate limits to prevent a high volume of requests from being created at once, but those limits did not stop Zendesk customers from flooding my inbox with thousands of messages in just a few hours.

“We recognize that our systems were leveraged against you in a distributed, many-against-one manner,” Camoens said. “We are actively investigating additional preventive measures. We are also advising customers experiencing this type of activity to follow our general security best practices and configure an authenticated ticket creation workflow.”

In all of the cases above, the messaging abuse would not have been possible if Zendesk customers validated support request email addresses prior to sending responses. Failing to do so may make it easier for Zendesk clients to handle customer support requests, but it also allows ne’er-do-wells to sully the sender’s brand in service of disruptive and malicious email floods.

The world’s largest and most disruptive botnet is now drawing a majority of its firepower from compromised Internet-of-Things (IoT) devices hosted on U.S. Internet providers like AT&T, Comcast and Verizon, new evidence suggests. Experts say the heavy concentration of infected devices at U.S. providers is complicating efforts to limit collateral damage from the botnet’s attacks, which shattered previous records this week with a brief traffic flood that clocked in at nearly 30 trillion bits of data per second.

Since its debut more than a year ago, the Aisuru botnet has steadily outcompeted virtually all other IoT-based botnets in the wild, with recent attacks siphoning Internet bandwidth from an estimated 300,000 compromised hosts worldwide.

The hacked systems that get subsumed into the botnet are mostly consumer-grade routers, security cameras, digital video recorders and other devices operating with insecure and outdated firmware, and/or factory-default settings. Aisuru’s owners are continuously scanning the Internet for these vulnerable devices and enslaving them for use in distributed denial-of-service (DDoS) attacks that can overwhelm targeted servers with crippling amounts of junk traffic.

As Aisuru’s size has mushroomed, so has its punch. In May 2025, KrebsOnSecurity was hit with a near-record 6.35 terabits per second (Tbps) attack from Aisuru, which was then the largest assault that Google’s DDoS protection service Project Shield had ever mitigated. Days later, Aisuru shattered that record with a data blast in excess of 11 Tbps.

By late September, Aisuru was publicly flexing DDoS capabilities topping 22 Tbps. Then on October 6, its operators heaved a whopping 29.6 terabits of junk data packets each second at a targeted host. Hardly anyone noticed because it appears to have been a brief test or demonstration of Aisuru’s capabilities: The traffic flood lasted less only a few seconds and was pointed at an Internet server that was specifically designed to measure large-scale DDoS attacks.

A measurement of an Oct. 6 DDoS believed to have been launched through multiple botnets operated by the owners of the Aisuru botnet. Image: DDoS Analyzer Community on Telegram.

Aisuru’s overlords aren’t just showing off. Their botnet is being blamed for a series of increasingly massive and disruptive attacks. Although recent assaults from Aisuru have targeted mostly ISPs that serve online gaming communities like Minecraft, those digital sieges often result in widespread collateral Internet disruption.

For the past several weeks, ISPs hosting some of the Internet’s top gaming destinations have been hit with a relentless volley of gargantuan attacks that experts say are well beyond the DDoS mitigation capabilities of most organizations connected to the Internet today.

Steven Ferguson is principal security engineer at Global Secure Layer (GSL), an ISP in Brisbane, Australia. GSL hosts TCPShield, which offers free or low-cost DDoS protection to more than 50,000 Minecraft servers worldwide. Ferguson told KrebsOnSecurity that on October 8, TCPShield was walloped with a blitz from Aisuru that flooded its network with more than 15 terabits of junk data per second.

Ferguson said that after the attack subsided, TCPShield was told by its upstream provider OVH that they were no longer welcome as a customer.

“This was causing serious congestion on their Miami external ports for several weeks, shown publicly via their weather map,” he said, explaining that TCPShield is now solely protected by GSL.

Traces from the recent spate of crippling Aisuru attacks on gaming servers can be still seen at the website blockgametracker.gg, which indexes the uptime and downtime of the top Minecraft hosts. In the following example from a series of data deluges on the evening of September 28, we can see an Aisuru botnet campaign briefly knocked TCPShield offline.

An Aisuru botnet attack on TCPShield (AS64199) on Sept. 28  can be seen in the giant downward spike in the middle of this uptime graphic. Image: grafana.blockgametracker.gg.

Paging through the same uptime graphs for other network operators listed shows almost all of them suffered brief but repeated outages around the same time. Here is the same uptime tracking for Minecraft servers on the network provider Cosmic (AS30456), and it shows multiple large dips that correspond to game server outages caused by Aisuru.

Multiple DDoS attacks from Aisuru can be seen against the Minecraft host Cosmic on Sept. 28. The sharp downward spikes correspond to brief but enormous attacks from Aisuru. Image: grafana.blockgametracker.gg.

BOTNETS R US

Ferguson said he’s been tracking Aisuru for about three months, and recently he noticed the botnet’s composition shifted heavily toward infected systems at ISPs in the United States. Ferguson shared logs from an attack on October 8 that indexed traffic by the total volume sent through each network provider, and the logs showed that 11 of the top 20 traffic sources were U.S. based ISPs.

AT&T customers were by far the biggest U.S. contributors to that attack, followed by botted systems on Charter Communications, Comcast, T-Mobile and Verizon, Ferguson found. He said the volume of data packets per second coming from infected IoT hosts on these ISPs is often so high that it has started to affect the quality of service that ISPs are able to provide to adjacent (non-botted) customers.

“The impact extends beyond victim networks,” Ferguson said. “For instance we have seen 500 gigabits of traffic via Comcast’s network alone. This amount of egress leaving their network, especially being so US-East concentrated, will result in congestion towards other services or content trying to be reached while an attack is ongoing.”

Roland Dobbins is principal engineer at Netscout. Dobbins said Ferguson is spot on, noting that while most ISPs have effective mitigations in place to handle large incoming DDoS attacks, many are far less prepared to manage the inevitable service degradation caused by large numbers of their customers suddenly using some or all available bandwidth to attack others.

“The outbound and cross-bound DDoS attacks can be just as disruptive as the inbound stuff,” Dobbin said. “We’re now in a situation where ISPs are routinely seeing terabit-per-second plus outbound attacks from their networks that can cause operational problems.”

“The crying need for effective and universal outbound DDoS attack suppression is something that is really being highlighted by these recent attacks,” Dobbins continued. “A lot of network operators are learning that lesson now, and there’s going to be a period ahead where there’s some scrambling and potential disruption going on.”

KrebsOnSecurity sought comment from the ISPs named in Ferguson’s report. Charter Communications pointed to a recent blog post on protecting its network, stating that Charter actively monitors for both inbound and outbound attacks, and that it takes proactive action wherever possible.

“In addition to our own extensive network security, we also aim to reduce the risk of customer connected devices contributing to attacks through our Advanced WiFi solution that includes Security Shield, and we make Security Suite available to our Internet customers,” Charter wrote in an emailed response to questions. “With the ever-growing number of devices connecting to networks, we encourage customers to purchase trusted devices with secure development and manufacturing practices, use anti-virus and security tools on their connected devices, and regularly download security patches.”

A spokesperson for Comcast responded, “Currently our network is not experiencing impacts and we are able to handle the traffic.”

9 YEARS OF MIRAI

Aisuru is built on the bones of malicious code that was leaked in 2016 by the original creators of the Mirai IoT botnet. Like Aisuru, Mirai quickly outcompeted all other DDoS botnets in its heyday, and obliterated previous DDoS attack records with a 620 gigabit-per-second siege that sidelined this website for nearly four days in 2016.

The Mirai botmasters likewise used their crime machine to attack mostly Minecraft servers, but with the goal of forcing Minecraft server owners to purchase a DDoS protection service that they controlled. In addition, they rented out slices of the Mirai botnet to paying customers, some of whom used it to mask the sources of other types of cybercrime, such as click fraud.

A depiction of the outages caused by the Mirai botnet attacks against the internet infrastructure firm Dyn on October 21, 2016. Source: Downdetector.com.

Dobbins said Aisuru’s owners also appear to be renting out their botnet as a distributed proxy network that cybercriminal customers anywhere in the world can use to anonymize their malicious traffic and make it appear to be coming from regular residential users in the U.S.

“The people who operate this botnet are also selling (it as) residential proxies,” he said. “And that’s being used to reflect application layer attacks through the proxies on the bots as well.”

The Aisuru botnet harkens back to its predecessor Mirai in another intriguing way. One of its owners is using the Telegram handle “9gigsofram,” which corresponds to the nickname used by the co-owner of a Minecraft server protection service called Proxypipe that was heavily targeted in 2016 by the original Mirai botmasters.

Robert Coelho co-ran Proxypipe back then along with his business partner Erik “9gigsofram” Buckingham, and has spent the past nine years fine-tuning various DDoS mitigation companies that cater to Minecraft server operators and other gaming enthusiasts. Coelho said he has no idea why one of Aisuru’s botmasters chose Buckingham’s nickname, but added that it might say something about how long this person has been involved in the DDoS-for-hire industry.

“The Aisuru attacks on the gaming networks these past seven day have been absolutely huge, and you can see tons of providers going down multiple times a day,” Coelho said.

Coelho said the 15 Tbps attack this week against TCPShield was likely only a portion of the total attack volume hurled by Aisuru at the time, because much of it would have been shoved through networks that simply couldn’t process that volume of traffic all at once. Such outsized attacks, he said, are becoming increasingly difficult and expensive to mitigate.

“It’s definitely at the point now where you need to be spending at least a million dollars a month just to have the network capacity to be able to deal with these attacks,” he said.

RAPID SPREAD

Aisuru has long been rumored to use multiple zero-day vulnerabilities in IoT devices to aid its rapid growth over the past year. XLab, the Chinese security company that was the first to profile Aisuru’s rise in 2024, warned last month that one of the Aisuru botmasters had compromised the firmware distribution website for Totolink, a maker of low-cost routers and other networking gear.

“Multiple sources indicate the group allegedly compromised a router firmware update server in April and distributed malicious scripts to expand the botnet,” XLab wrote on September 15. “The node count is currently reported to be around 300,000.”

A malicious script implanted into a Totolink update server in April 2025. Image: XLab.

Aisuru’s operators received an unexpected boost to their crime machine in August when the U.S. Department Justice charged the alleged proprietor of Rapper Bot, a DDoS-for-hire botnet that competed directly with Aisuru for control over the global pool of vulnerable IoT systems.

Once Rapper Bot was dismantled, Aisuru’s curators moved quickly to commandeer vulnerable IoT devices that were suddenly set adrift by the government’s takedown, Dobbins said.

“Folks were arrested and Rapper Bot control servers were seized and that’s great, but unfortunately the botnet’s attack assets were then pieced out by the remaining botnets,” he said. “The problem is, even if those infected IoT devices are rebooted and cleaned up, they will still get re-compromised by something else generally within minutes of being plugged back in.”

A screenshot shared by XLabs showing the Aisuru botmasters recently celebrating a record-breaking 7.7 Tbps DDoS. The user at the top has adopted the name “Ethan J. Foltz” in a mocking tribute to the alleged Rapper Bot operator who was arrested and charged in August 2025.

BOTMASTERS AT LARGE

XLab’s September blog post cited multiple unnamed sources saying Aisuru is operated by three cybercriminals: “Snow,” who’s responsible for botnet development; “Tom,” tasked with finding new vulnerabilities; and “Forky,” responsible for botnet sales.

KrebsOnSecurity interviewed Forky in our May 2025 story about the record 6.3 Tbps attack from Aisuru. That story identified Forky as a 21-year-old man from Sao Paulo, Brazil who has been extremely active in the DDoS-for-hire scene since at least 2022. The FBI has seized Forky’s DDoS-for-hire domains several times over the years.

Like the original Mirai botmasters, Forky also operates a DDoS mitigation service called Botshield. Forky declined to discuss the makeup of his ISP’s clientele, or to clarify whether Botshield was more of a hosting provider or a DDoS mitigation firm. However, Forky has posted on Telegram about Botshield successfully mitigating large DDoS attacks launched against other DDoS-for-hire services.

In our previous interview, Forky acknowledged being involved in the development and marketing of Aisuru, but denied participating in attacks launched by the botnet.

Reached for comment earlier this month, Forky continued to maintain his innocence, claiming that he also is still trying to figure out who the current Aisuru botnet operators are in real life (Forky said the same thing in our May interview).

But after a week of promising juicy details, Forky came up empty-handed once again. Suspecting that Forky was merely being coy, I asked him how someone so connected to the DDoS-for-hire world could still be mystified on this point, and suggested that his inability or unwillingness to blame anyone else for Aisuru would not exactly help his case.

At this, Forky verbally bristled at being pressed for more details, and abruptly terminated our interview.

“I’m not here to be threatened with ignorance because you are stressed,” Forky replied. “They’re blaming me for those new attacks. Pretty much the whole world (is) due to your blog.”

A cybercriminal group that used voice phishing attacks to siphon more than a billion records from Salesforce customers earlier this year has launched a website that threatens to publish data stolen from dozens of Fortune 500 firms if they refuse to pay a ransom. The group also claimed responsibility for a recent breach involving Discord user data, and for stealing terabytes of sensitive files from thousands of customers of the enterprise software maker Red Hat.

The new extortion website tied to ShinyHunters (UNC6040), which threatens to publish stolen data unless Salesforce or individual victim companies agree to pay a ransom.

In May 2025, a prolific and amorphous English-speaking cybercrime group known as ShinyHunters launched a social engineering campaign that used voice phishing to trick targets into connecting a malicious app to their organization’s Salesforce portal.

The first real details about the incident came in early June, when the Google Threat Intelligence Group (GTIG) warned that ShinyHunters — tracked by Google as UNC6040 — was extorting victims over their stolen Salesforce data, and that the group was poised to launch a data leak site to publicly shame victim companies into paying a ransom to keep their records private. A month later, Google acknowledged that one of its own corporate Salesforce instances was impacted in the voice phishing campaign.

Last week, a new victim shaming blog dubbed “Scattered LAPSUS$ Hunters” began publishing the names of companies that had customer Salesforce data stolen as a result of the May voice phishing campaign.

“Contact us to negotiate this ransom or all your customers data will be leaked,” the website stated in a message to Salesforce. “If we come to a resolution all individual extortions against your customers will be withdrawn from. Nobody else will have to pay us, if you pay, Salesforce, Inc.”

Below that message were more than three dozen entries for companies that allegedly had Salesforce data stolen, including Toyota, FedEx, Disney/Hulu, and UPS. The entries for each company specified the volume of stolen data available, as well as the date that the information was retrieved (the stated breach dates range between May and September 2025).

Image: Mandiant.

On October 5, the Scattered LAPSUS$ Hunters victim shaming and extortion blog announced that the group was responsible for a breach in September involving a GitLab server used by Red Hat that contained more than 28,000 Git code repositories, including more than 5,000 Customer Engagement Reports (CERs).

“Alot of folders have their client’s secrets such as artifactory access tokens, git tokens, azure, docker (redhat docker, azure containers, dockerhub), their client’s infrastructure details in the CERs like the audits that were done for them, and a whole LOT more, etc.,” the hackers claimed.

Their claims came several days after a previously unknown hacker group calling itself the Crimson Collective took credit for the Red Hat intrusion on Telegram.

Red Hat disclosed on October 2 that attackers had compromised a company GitLab server, and said it was in the process of notifying affected customers.

“The compromised GitLab instance housed consulting engagement data, which may include, for example, Red Hat’s project specifications, example code snippets, internal communications about consulting services, and limited forms of business contact information,” Red Hat wrote.

Separately, Discord has started emailing users affected by another breach claimed by ShinyHunters. Discord said an incident on September 20 at a “third-party customer service provider” impacted a “limited number of users” who communicated with Discord customer support or Trust & Safety teams. The information included Discord usernames, emails, IP address, the last four digits of any stored payment cards, and government ID images submitted during age verification appeals.

The Scattered Lapsus$ Hunters claim they will publish data stolen from Salesforce and its customers if ransom demands aren’t paid by October 10. The group also claims it will soon begin extorting hundreds more organizations that lost data in August after a cybercrime group stole vast amounts of authentication tokens from Salesloft, whose AI chatbot is used by many corporate websites to convert customer interaction into Salesforce leads.

In a communication sent to customers today, Salesforce emphasized that the theft of any third-party Salesloft data allegedly stolen by ShinyHunters did not originate from a vulnerability within the core Salesforce platform. The company also stressed that it has no plans to meet any extortion demands.

“Salesforce will not engage, negotiate with, or pay any extortion demand,” the message to customers read. “Our focus is, and remains, on defending our environment, conducting thorough forensic analysis, supporting our customers, and working with law enforcement and regulatory authorities.”

The GTIG tracked the group behind the Salesloft data thefts as UNC6395, and says the group has been observed harvesting the data for authentication tokens tied to a range of cloud services like Snowflake and Amazon’s AWS.

Google catalogs Scattered Lapsus$ Hunters by so many UNC names (throw in UNC6240 for good measure) because it is thought to be an amalgamation of three hacking groups — Scattered Spider, Lapsus$ and ShinyHunters. The members of these groups hail from many of the same chat channels on the Com, a mostly English-language cybercriminal community that operates across an ocean of Telegram and Discord servers.

The Scattered Lapsus$ Hunters darknet blog is currently offline. The outage appears to have coincided with the disappearance of the group’s new clearnet blog — breachforums[.]hn — which vanished after shifting its Domain Name Service (DNS) servers from DDoS-Guard to Cloudflare.

But before it died, the websites disclosed that hackers were exploiting a critical zero-day vulnerability in Oracle’s E-Business Suite software. Oracle has since confirmed that a security flaw tracked as CVE-2025-61882 allows attackers to perform unauthenticated remote code execution, and is urging customers to apply an emergency update to address the weakness.

Mandiant’s Charles Carmakal shared on LinkedIn that CVE-2025-61882 was initially exploited in August 2025 by the Clop ransomware gang to steal data from Oracle E-Business Suite servers. Bleeping Computer writes that news of the Oracle zero-day first surfaced on the Scattered Lapsus$ Hunters blog, which published a pair of scripts that were used to exploit vulnerable Oracle E-Business Suite instances.

On Monday evening, KrebsOnSecurity received a malware-laced message from a reader that threatened physical violence unless their unstated demands were met. The missive, titled “Shiny hunters,” contained the hashtag $LAPSU$$SCATEREDHUNTER, and urged me to visit a page on limewire[.]com to view their demands.

A screenshot of the phishing message linking to a malicious trojan disguised as a Windows screensaver file.

KrebsOnSecurity did not visit this link, but instead forwarded it to Mandiant, which confirmed that similar menacing missives were sent to employees at Mandiant and other security firms around the same time.

The link in the message fetches a malicious trojan disguised as a Windows screensaver file (Virustotal’s analysis on this malware is here). Simply viewing the booby-trapped screensaver on a Windows PC is enough to cause the bundled trojan to launch in the background.

Mandiant’s Austin Larsen said the trojan is a commercially available backdoor known as ASYNCRAT, a .NET-based backdoor that communicates using a custom binary protocol over TCP, and can execute shell commands and download plugins to extend its features.

A scan of the malicious screensaver file at Virustotal.com shows it is detected as bad by nearly a dozen security and antivirus tools.

“Downloaded plugins may be executed directly in memory or stored in the registry,” Larsen wrote in an analysis shared via email. “Capabilities added via plugins include screenshot capture, file transfer, keylogging, video capture, and cryptocurrency mining. ASYNCRAT also supports a plugin that targets credentials stored by Firefox and Chromium-based web browsers.”

Malware-laced targeted emails are not out of character for certain members of the Scattered Lapsus$ Hunters, who have previously harassed and threatened security researchers and even law enforcement officials who are investigating and warning about the extent of their attacks.

With so many big data breaches and ransom attacks now coming from cybercrime groups operating on the Com, law enforcement agencies on both sides of the pond are under increasing pressure to apprehend the criminal hackers involved. In late September, prosecutors in the U.K. charged two alleged Scattered Spider members aged 18 and 19 with extorting at least $115 million in ransom payments from companies victimized by data theft.

U.S. prosecutors heaped their own charges on the 19 year-old in that duo — U.K. resident Thalha Jubair — who is alleged to have been involved in data ransom attacks against Marks & Spencer and Harrods, the British food retailer Co-op Group, and the 2023 intrusions at MGM Resorts and Caesars Entertainment. Jubair also was allegedly a key member of LAPSUS$, a cybercrime group that broke into dozens of technology companies beginning in late 2021.

A Mastodon post by Kevin Beaumont, lamenting the prevalence of major companies paying millions to extortionist teen hackers, refers derisively to Thalha Jubair as a part of an APT threat known as “Advanced Persistent Teenagers.”

In August, convicted Scattered Spider member and 20-year-old Florida man Noah Michael Urban was sentenced to 10 years in federal prison and ordered to pay roughly $13 million in restitution to victims.

In April 2025, a 23-year-old Scottish man thought to be an early Scattered Spider member was extradited from Spain to the U.S., where he is facing charges of wire fraud, conspiracy and identity theft. U.S. prosecutors allege Tyler Robert Buchanan and co-conspirators hacked into dozens of companies in the United States and abroad, and that he personally controlled more than $26 million stolen from victims.

Update, Oct. 8, 8:59 a.m. ET: A previous version of this story incorrectly referred to the malware sent by the reader as a Windows screenshot file. Rather, it is a Windows screensaver file.

Ambitious, suspected Chinese hackers with a slew of goals — stealing intellectual property, mining intelligence on national security and trade, developing avenues for future advanced cyberattacks — have been setting up shop inside U.S. target networks for exceptionally long stretches of time, in a breach that the researchers who uncovered it said could present problems for years to come.

Mandiant and Google Threat Intelligence Group (GTIG) researchers described the campaign as exceptionally sophisticated, stealthy and complex, calling those behind it a “next-level threat.” But they don’t yet have a full handle on who the hackers are behind the malware they’ve dubbed Brickstorm, or how far it stretches. A blog post the company posted Wednesday sheds light on the group.

The primary targets are legal services organizations and tech companies that provide security services, the researchers said. But the hackers aren’t limiting their interest to the primary targets, since they’ve used that access to infiltrate “downstream” customers. The researchers declined to describe those downstream customers, or say whether U.S. federal agencies are among those targeted. A great many of them don’t know yet that they’re victims, they said.

By stealing intellectual property from security-as-a-service (SaaS) firms, the hackers aim to find future zero-day vulnerabilities, a kind of vulnerability that is previously unknown and unpatched and thus highly prized, in order to enable more attacks down the line, the researchers from Mandiant and its parent company Google said.

The researchers declined to comment on possible Chinese government agency connections. But they see overlap with Chinese hacking groups like the one they’ve labeled UNC5221 — perhaps best known for exploiting Ivanti flaws, and a group that Mandiant and GTIIG described as the “most prevalent” Chinese-centered threat group right now — and the one Microsoft calls Silk Typhoon, which researchers warned recently has been ramping up its attacks this year, with targets including IT supply chains and the cloud. Silk Typhoon is believed to be Chinese government-sponsored. 

The company has also developed a tool for potential victims to discover if they’ve been affected by Brickstorm activity, which Google experts indicated is a distinct possibility that could impact scores of organizations over the coming weeks.

“We have no doubt that organizations will use our tools to hunt for this adversary, and they will find evidence of compromise in their environments,” Charles Carmakal, chief technology officer at Mandiant Consulting, told reporters briefed on the blog post. “And it may be active compromises, it might be historic compromises, but many of our organizations are going to discover that they were dealing with this adversary.” 

Sneaky, sneaky

The campaign’s average “dwell time” is 400 days, they said, compared to dwell times more commonly measured in days or weeks. 

Several features obscure Brickstorm activity. “It’s very hard to detect them and to investigate them,” said Austin Larsen, principal threat analyst at GTIG.

The hackers target systems that don’t support defenses for finding and tracking threats on endpoints, such as laptops or cell phones. Examples of target systems that don’t support that kind of endpoint detection and response (EDR) include email security gateways or vulnerability scanners. They consistently target VMware vCenter and ESXi hosts, according to the blog post.

The researchers also never see overlap between the internet protocols of the attackers between victims, Larsen said, or another way of identifying attackers: “The hashes when they land on this are different for essentially every system.”

Brickstorm attackers also “clean up after themselves” at times, Carmakal said. “Brickstorm may not exist in a victim environment today, but it could have been there for a year and a half. It might have been deleted back in April this year, back in January this year,” he said.

What they want

Brickstorm also isn’t just about one goal. “It’s an intelligence operation, but not just an intelligence operation,” said John Hultquist, chief analyst at GTIG. “This is a long-term play.”

The hackers are primarily compromising victims through zero-days, but they’re aiming to uncover new ones, too, by going through companies’ proprietary source code. That gives them multiple ways to penetrate new victim networks.

The Brickstorm hackers “hit the SaaS providers, who either hold data for people, or they have some connectivity to downstream,” Hultquist said. Or he said the group can “get a hold of the technology source code and leverage that source code information to gain access or to build out exploits in that technology, which would then give [them] basically a skeleton key to that technology.”

But its victims can be even more precise than that. “As part of this campaign, we observed in some organizations — including some legal organizations — we observed the actor searching the emails of very specific individuals,” Larsen said. The hackers have focused on collecting espionage on international trade and national security from those organizations.

Google has been tracking Brickstorm for a while now. This spring, Belgian cybersecurity company NVISO also shined the spotlight on Brickstorm variants spying on European businesses. Google’s latest blog post identifies Brickstorm activity as far more extensive than previously described.

The response

Mandiant and GTIG have notified U.S. federal agencies and international governments about the campaign.

The tool is a scanner script that can be used on Unix systems, even if YARA (a common security tool used to find and identify malware) isn’t installed. This script is designed to do the same type of search as a specific YARA rule by looking for certain words and patterns that are unique to the Brickstorm backdoor.

“The most important thing here is, if you find Brickstorm, you really need to do a very thorough enterprise investigation, because the adversary that’s dropping this is a very, very advanced adversary that is known for stealing intellectual property from organizations,” Carmakal said. “It’s known for using access from victim companies to get into downstream customer environments.”

It’s all a “very, very significant threat campaign [that’s] very, very hard to defend against in tech,” Carmakal said.

Updated 9/24/25: with additional information about past Brickstorm reporting.

The post Brickstorm malware powering ‘next-level’ Chinese cyberespionage campaign appeared first on CyberScoop.

At least 187 code packages made available through the JavaScript repository NPM have been infected with a self-replicating worm that steals credentials from developers and publishes those secrets on GitHub, experts warn. The malware, which briefly infected multiple code packages from the security vendor CrowdStrike, steals and publishes even more credentials every time an infected package is installed.

Image: https://en.wikipedia.org/wiki/Sandworm_(Dune)

The novel malware strain is being dubbed Shai-Hulud — after the name for the giant sandworms in Frank Herbert’s Dune novel series — because it publishes any stolen credentials in a new public GitHub repository that includes the name “Shai-Hulud.”

“When a developer installs a compromised package, the malware will look for a npm token in the environment,” said Charlie Eriksen, a researcher for the Belgian security firm Aikido. “If it finds it, it will modify the 20 most popular packages that the npm token has access to, copying itself into the package, and publishing a new version.”

At the center of this developing maelstrom are code libraries available on NPM (short for “Node Package Manager”), which acts as a central hub for JavaScript development and provides the latest updates to widely-used JavaScript components.

The Shai-Hulud worm emerged just days after unknown attackers launched a broad phishing campaign that spoofed NPM and asked developers to “update” their multi-factor authentication login options. That attack led to malware being inserted into at least two-dozen NPM code packages, but the outbreak was quickly contained and was narrowly focused on siphoning cryptocurrency payments.

Image: aikido.dev

In late August, another compromise of an NPM developer resulted in malware being added to “nx,” an open-source code development toolkit with as many as six million weekly downloads. In the nx compromise, the attackers introduced code that scoured the user’s device for authentication tokens from programmer destinations like GitHub and NPM, as well as SSH and API keys. But instead of sending those stolen credentials to a central server controlled by the attackers, the malicious nx code created a new public repository in the victim’s GitHub account, and published the stolen data there for all the world to see and download.

Last month’s attack on nx did not self-propagate like a worm, but this Shai-Hulud malware does and bundles reconnaissance tools to assist in its spread. Namely, it uses the open-source tool TruffleHog to search for exposed credentials and access tokens on the developer’s machine. It then attempts to create new GitHub actions and publish any stolen secrets.

“Once the first person got compromised, there was no stopping it,” Aikido’s Eriksen told KrebsOnSecurity. He said the first NPM package compromised by this worm appears to have been altered on Sept. 14, around 17:58 UTC.

The security-focused code development platform socket.dev reports the Shai-Halud attack briefly compromised at least 25 NPM code packages managed by CrowdStrike. Socket.dev said the affected packages were quickly removed by the NPM registry.

In a written statement shared with KrebsOnSecurity, CrowdStrike said that after detecting several malicious packages in the public NPM registry, the company swiftly removed them and rotated its keys in public registries.

“These packages are not used in the Falcon sensor, the platform is not impacted and customers remain protected,” the statement reads, referring to the company’s widely-used endpoint threat detection service. “We are working with NPM and conducting a thorough investigation.”

A writeup on the attack from StepSecurity found that for cloud-specific operations, the malware enumerates AWS, Azure and Google Cloud Platform secrets. It also found the entire attack design assumes the victim is working in a Linux or macOS environment, and that it deliberately skips Windows systems.

StepSecurity said Shai-Hulud spreads by using stolen NPM authentication tokens, adding its code to the top 20 packages in the victim’s account.

“This creates a cascading effect where an infected package leads to compromised maintainer credentials, which in turn infects all other packages maintained by that user,” StepSecurity’s Ashish Kurmi wrote.

Eriksen said Shai-Hulud is still propagating, although its spread seems to have waned in recent hours.

“I still see package versions popping up once in a while, but no new packages have been compromised in the last ~6 hours,” Eriksen said. “But that could change now as the east coast starts working. I would think of this attack as a ‘living’ thing almost, like a virus. Because it can lay dormant for a while, and if just one person is suddenly infected by accident, they could restart the spread. Especially if there’s a super-spreader attack.”

For now, it appears that the web address the attackers were using to exfiltrate collected data was disabled due to rate limits, Eriksen said.

Nicholas Weaver is a researcher with the International Computer Science Institute, a nonprofit in Berkeley, Calif. Weaver called the Shai-Hulud worm “a supply chain attack that conducts a supply chain attack.” Weaver said NPM (and all other similar package repositories) need to immediately switch to a publication model that requires explicit human consent for every publication request using a phish-proof 2FA method.

“Anything less means attacks like this are going to continue and become far more common, but switching to a 2FA method would effectively throttle these attacks before they can spread,” Weaver said. “Allowing purely automated processes to update the published packages is now a proven recipe for disaster.”

Microsoft Corp. today issued security updates to fix more than 80 vulnerabilities in its Windows operating systems and software. There are no known “zero-day” or actively exploited vulnerabilities in this month’s bundle from Redmond, which nevertheless includes patches for 13 flaws that earned Microsoft’s most-dire “critical” label. Meanwhile, both Apple and Google recently released updates to fix zero-day bugs in their devices.

Microsoft assigns security flaws a “critical” rating when malware or miscreants can exploit them to gain remote access to a Windows system with little or no help from users. Among the more concerning critical bugs quashed this month is CVE-2025-54918. The problem here resides with Windows NTLM, or NT LAN Manager, a suite of code for managing authentication in a Windows network environment.

Redmond rates this flaw as “Exploitation More Likely,” and although it is listed as a privilege escalation vulnerability, Kev Breen at Immersive says this one is actually exploitable over the network or the Internet.

“From Microsoft’s limited description, it appears that if an attacker is able to send specially crafted packets over the network to the target device, they would have the ability to gain SYSTEM-level privileges on the target machine,” Breen said. “The patch notes for this vulnerability state that ‘Improper authentication in Windows NTLM allows an authorized attacker to elevate privileges over a network,’ suggesting an attacker may already need to have access to the NTLM hash or the user’s credentials.”

Breen said another patch — CVE-2025-55234, a 8.8 CVSS-scored flaw affecting the Windows SMB client for sharing files across a network — also is listed as privilege escalation bug but is likewise remotely exploitable. This vulnerability was publicly disclosed prior to this month.

“Microsoft says that an attacker with network access would be able to perform a replay attack against a target host, which could result in the attacker gaining additional privileges, which could lead to code execution,” Breen noted.

CVE-2025-54916 is an “important” vulnerability in Windows NTFS — the default filesystem for all modern versions of Windows — that can lead to remote code execution. Microsoft likewise thinks we are more than likely to see exploitation of this bug soon: The last time Microsoft patched an NTFS bug was in March 2025 and it was already being exploited in the wild as a zero-day.

“While the title of the CVE says ‘Remote Code Execution,’ this exploit is not remotely exploitable over the network, but instead needs an attacker to either have the ability to run code on the host or to convince a user to run a file that would trigger the exploit,” Breen said. “This is commonly seen in social engineering attacks, where they send the user a file to open as an attachment or a link to a file to download and run.”

Critical and remote code execution bugs tend to steal all the limelight, but Tenable Senior Staff Research Engineer Satnam Narang notes that nearly half of all vulnerabilities fixed by Microsoft this month are privilege escalation flaws that require an attacker to have gained access to a target system first before attempting to elevate privileges.

“For the third time this year, Microsoft patched more elevation of privilege vulnerabilities than remote code execution flaws,” Narang observed.

On Sept. 3, Google fixed two flaws that were detected as exploited in zero-day attacks, including CVE-2025-38352, an elevation of privilege in the Android kernel, and CVE-2025-48543, also an elevation of privilege problem in the Android Runtime component.

Also, Apple recently patched its seventh zero-day (CVE-2025-43300) of this year. It was part of an exploit chain used along with a vulnerability in the WhatsApp (CVE-2025-55177) instant messenger to hack Apple devices. Amnesty International reports that the two zero-days have been used in “an advanced spyware campaign” over the past 90 days. The issue is fixed in iOS 18.6.2, iPadOS 18.6.2, iPadOS 17.7.10, macOS Sequoia 15.6.1, macOS Sonoma 14.7.8, and macOS Ventura 13.7.8.

The SANS Internet Storm Center has a clickable breakdown of each individual fix from Microsoft, indexed by severity and CVSS score. Enterprise Windows admins involved in testing patches before rolling them out should keep an eye on askwoody.com, which often has the skinny on wonky updates.

AskWoody also reminds us that we’re now just two months out from Microsoft discontinuing free security updates for Windows 10 computers. For those interested in safely extending the lifespan and usefulness of these older machines, check out last month’s Patch Tuesday coverage for a few pointers.

As ever, please don’t neglect to back up your data (if not your entire system) at regular intervals, and feel free to sound off in the comments if you experience problems installing any of these fixes.

At least 18 popular JavaScript code packages that are collectively downloaded more than two billion times each week were briefly compromised with malicious software today, after a developer involved in maintaining the projects was phished. The attack appears to have been quickly contained and was narrowly focused on stealing cryptocurrency. But experts warn that a similar attack with a slightly more nefarious payload could lead to a disruptive malware outbreak that is far more difficult to detect and restrain.

This phishing email lured a developer into logging in at a fake NPM website and supplying a one-time token for two-factor authentication. The phishers then used that developer’s NPM account to add malicious code to at least 18 popular JavaScript code packages.

Aikido is a security firm in Belgium that monitors new code updates to major open-source code repositories, scanning any code updates for suspicious and malicious code. In a blog post published today, Aikido said its systems found malicious code had been added to at least 18 widely-used code libraries available on NPM (short for) “Node Package Manager,” which acts as a central hub for JavaScript development and the latest updates to widely-used JavaScript components.

JavaScript is a powerful web-based scripting language used by countless websites to build a more interactive experience with users, such as entering data into a form. But there’s no need for each website developer to build a program from scratch for entering data into a form when they can just reuse already existing packages of code at NPM that are specifically designed for that purpose.

Unfortunately, if cybercriminals manage to phish NPM credentials from developers, they can introduce malicious code that allows attackers to fundamentally control what people see in their web browser when they visit a website that uses one of the affected code libraries.

According to Aikido, the attackers injected a piece of code that silently intercepts cryptocurrency activity in the browser, “manipulates wallet interactions, and rewrites payment destinations so that funds and approvals are redirected to attacker-controlled accounts without any obvious signs to the user.”

“This malware is essentially a browser-based interceptor that hijacks both network traffic and application APIs,” Aikido researcher Charlie Eriksen wrote. “What makes it dangerous is that it operates at multiple layers: Altering content shown on websites, tampering with API calls, and manipulating what users’ apps believe they are signing. Even if the interface looks correct, the underlying transaction can be redirected in the background.”

Aikido said it used the social network Bsky to notify the affected developer, Josh Junon, who quickly replied that he was aware of having just been phished. The phishing email that Junon fell for was part of a larger campaign that spoofed NPM and told recipients they were required to update their two-factor authentication (2FA) credentials. The phishing site mimicked NPM’s login page, and intercepted Junon’s credentials and 2FA token. Once logged in, the phishers then changed the email address on file for Junon’s NPM account, temporarily locking him out.

Aikido notified the maintainer on Bluesky, who replied at 15:15 UTC that he was aware of being compromised, and starting to clean up the compromised packages.

Junon also issued a mea culpa on HackerNews, telling the community’s coder-heavy readership, “Hi, yep I got pwned.”

“It looks and feels a bit like a targeted attack,” Junon wrote. “Sorry everyone, very embarrassing.”

Philippe Caturegli, “chief hacking officer” at the security consultancy Seralys, observed that the attackers appear to have registered their spoofed website — npmjs[.]help — just two days before sending the phishing email. The spoofed website used services from dnsexit[.]com, a “dynamic DNS” company that also offers “100% free” domain names that can instantly be pointed at any IP address controlled by the user.

Junon’s mea cupla on Hackernews today listed the affected packages.

Caturegli said it’s remarkable that the attackers in this case were not more ambitious or malicious with their code modifications.

“The crazy part is they compromised billions of websites and apps just to target a couple of cryptocurrency things,” he said. “This was a supply chain attack, and it could easily have been something much worse than crypto harvesting.”

Aikido’s Eriksen agreed, saying countless websites dodged a bullet because this incident was handled in a matter of hours. As an example of how these supply-chain attacks can escalate quickly, Eriksen pointed to another compromise of an NPM developer in late August that added malware to “nx,” an open-source code development toolkit with as many as six million weekly downloads.

In the nx compromise, the attackers introduced code that scoured the user’s device for authentication tokens from programmer destinations like GitHub and NPM, as well as SSH and API keys. But instead of sending those stolen credentials to a central server controlled by the attackers, the malicious code created a new public repository in the victim’s GitHub account, and published the stolen data there for all the world to see and download.

Eriksen said coding platforms like GitHub and NPM should be doing more to ensure that any new code commits for broadly-used packages require a higher level of attestation that confirms the code in question was in fact submitted by the person who owns the account, and not just by that person’s account.

“More popular packages should require attestation that it came through trusted provenance and not just randomly from some location on the Internet,” Eriksen said. “Where does the package get uploaded from, by GitHub in response to a new pull request into the main branch, or somewhere else? In this case, they didn’t compromise the target’s GitHub account. They didn’t touch that. They just uploaded a modified version that didn’t come where it’s expected to come from.”

Eriksen said code repository compromises can be devastating for developers, many of whom end up abandoning their projects entirely after such an incident.

“It’s unfortunate because one thing we’ve seen is people have their projects get compromised and they say, ‘You know what, I don’t have the energy for this and I’m just going to deprecate the whole package,'” Eriksen said.

Kevin Beaumont, a frequently quoted security expert who writes about security incidents at the blog doublepulsar.com, has been following this story closely today in frequent updates to his account on Mastodon. Beaumont said the incident is a reminder that much of the planet still depends on code that is ultimately maintained by an exceedingly small number of people who are mostly overburdened and under-resourced.

“For about the past 15 years every business has been developing apps by pulling in 178 interconnected libraries written by 24 people in a shed in Skegness,” Beaumont wrote on Mastodon. “For about the past 2 years orgs have been buying AI vibe coding tools, where some exec screams ‘make online shop’ into a computer and 389 libraries are added and an app is farted out. The output = if you want to own the world’s companies, just phish one guy in Skegness.”

Image: https://infosec.exchange/@GossiTheDog@cyberplace.social.

Aikido recently launched a product that aims to help development teams ensure that every code library used is checked for malware before it can be used or installed. Nicholas Weaver, a researcher with the International Computer Science Institute, a nonprofit in Berkeley, Calif., said Aikido’s new offering exists because many organizations are still one successful phishing attack away from a supply-chain nightmare.

Weaver said these types of supply-chain compromises will continue as long as people responsible for maintaining widely-used code continue to rely on phishable forms of 2FA.

“NPM should only support phish-proof authentication,” Weaver said, referring to physical security keys that are phish-proof — meaning that even if phishers manage to steal your username and password, they still can’t log in to your account without also possessing that physical key.

“All critical infrastructure needs to use phish-proof 2FA, and given the dependencies in modern software, archives such as NPM are absolutely critical infrastructure,” Weaver said. “That NPM does not require that all contributor accounts use security keys or similar 2FA methods should be considered negligence.”

The recent mass-theft of authentication tokens from Salesloft, whose AI chatbot is used by a broad swath of corporate America to convert customer interaction into Salesforce leads, has left many companies racing to invalidate the stolen credentials before hackers can exploit them. Now Google warns the breach goes far beyond access to Salesforce data, noting the hackers responsible also stole valid authentication tokens for hundreds of online services that customers can integrate with Salesloft, including Slack, Google Workspace, Amazon S3, Microsoft Azure, and OpenAI.

Salesloft says its products are trusted by 5,000+ customers. Some of the bigger names are visible on the company’s homepage.

Salesloft disclosed on August 20 that, “Today, we detected a security issue in the Drift application,” referring to the technology that powers an AI chatbot used by so many corporate websites. The alert urged customers to re-authenticate the connection between the Drift and Salesforce apps to invalidate their existing authentication tokens, but it said nothing then to indicate those tokens had already been stolen.

On August 26, the Google Threat Intelligence Group (GTIG) warned that unidentified hackers tracked as UNC6395 used the access tokens stolen from Salesloft to siphon large amounts of data from numerous corporate Salesforce instances. Google said the data theft began as early as Aug. 8, 2025 and lasted through at least Aug. 18, 2025, and that the incident did not involve any vulnerability in the Salesforce platform.

Google said the attackers have been sifting through the massive data haul for credential materials such as AWS keys, VPN credentials, and credentials to the cloud storage provider Snowflake.

“If successful, the right credentials could allow them to further compromise victim and client environments, as well as pivot to the victim’s clients or partner environments,” the GTIG report stated.

The GTIG updated its advisory on August 28 to acknowledge the attackers used the stolen tokens to access email from “a very small number of Google Workspace accounts” that were specially configured to integrate with Salesloft. More importantly, it warned organizations to immediately invalidate all tokens stored in or connected to their Salesloft integrations — regardless of the third-party service in question.

“Given GTIG’s observations of data exfiltration associated with the campaign, organizations using Salesloft Drift to integrate with third-party platforms (including but not limited to Salesforce) should consider their data compromised and are urged to take immediate remediation steps,” Google advised.

On August 28, Salesforce blocked Drift from integrating with its platform, and with its productivity platforms Slack and Pardot.

The Salesloft incident comes on the heels of a broad social engineering campaign that used voice phishing to trick targets into connecting a malicious app to their organization’s Salesforce portal. That campaign led to data breaches and extortion attacks affecting a number of companies including Adidas, Allianz Life and Qantas.

On August 5, Google disclosed that one of its corporate Salesforce instances was compromised by the attackers, which the GTIG has dubbed UNC6040 (“UNC” stands for “uncategorized threat group”). Google said the extortionists consistently claimed to be the threat group ShinyHunters, and that the group appeared to be preparing to escalate its extortion attacks by launching a data leak site.

ShinyHunters is an amorphous threat group known for using social engineering to break into cloud platforms and third-party IT providers, and for posting dozens of stolen databases to cybercrime communities like the now-defunct Breachforums.

The ShinyHunters brand dates back to 2020, and the group has been credited with or taken responsibility for dozens of data leaks that exposed hundreds of millions of breached records. The group’s member roster is thought to be somewhat fluid, drawing mainly from active denizens of the Com, a mostly English-language cybercrime community scattered across an ocean of Telegram and Discord servers.

Recorded Future’s Alan Liska told Bleeping Computer that the overlap in the “tools, techniques and procedures” used by ShinyHunters and the Scattered Spider extortion group likely indicate some crossover between the two groups.

To muddy the waters even further, on August 28 a Telegram channel that now has nearly 40,000 subscribers was launched under the intentionally confusing banner “Scattered LAPSUS$ Hunters 4.0,” wherein participants have repeatedly claimed responsibility for the Salesloft hack without actually sharing any details to prove their claims.

The Telegram group has been trying to attract media attention by threatening security researchers at Google and other firms. It also is using the channel’s sudden popularity to promote a new cybercrime forum called “Breachstars,” which they claim will soon host data stolen from victim companies who refuse to negotiate a ransom payment.

The “Scattered Lapsus$ Hunters 4.0” channel on Telegram now has roughly 40,000 subscribers.

But Austin Larsen, a principal threat analyst at Google’s threat intelligence group, said there is no compelling evidence to attribute the Salesloft activity to ShinyHunters or to other known groups at this time.

“Their understanding of the incident seems to come from public reporting alone,” Larsen told KrebsOnSecurity, referring to the most active participants in the Scattered LAPSUS$ Hunters 4.0 Telegram channel.

Joshua Wright, a senior technical director at Counter Hack, is credited with coining the term “authorization sprawl” to describe one key reason that social engineering attacks from groups like Scattered Spider and ShinyHunters so often succeed: They abuse legitimate user access tokens to move seamlessly between on-premises and cloud systems.

Wright said this type of attack chain often goes undetected because the attacker sticks to the resources and access already allocated to the user.

“Instead of the conventional chain of initial access, privilege escalation and endpoint bypass, these threat actors are using centralized identity platforms that offer single sign-on (SSO) and integrated authentication and authorization schemes,” Wright wrote in a June 2025 column. “Rather than creating custom malware, attackers use the resources already available to them as authorized users.”

It remains unclear exactly how the attackers gained access to all Salesloft Drift authentication tokens. Salesloft announced on August 27 that it hired Mandiant, Google Cloud’s incident response division, to investigate the root cause(s).

“We are working with Salesloft Drift to investigate the root cause of what occurred and then it’ll be up to them to publish that,” Mandiant Consulting CTO Charles Carmakal told Cyberscoop. “There will be a lot more tomorrow, and the next day, and the next day.”

Last month, KrebsOnSecurity tracked the sudden emergence of hundreds of polished online gaming and wagering websites that lure people with free credits and eventually abscond with any cryptocurrency funds deposited by players. We’ve since learned that these scam gambling sites have proliferated thanks to a new Russian affiliate program called “Gambler Panel” that bills itself as a “soulless project that is made for profit.”

A machine-translated version of Gambler Panel’s affiliate website.

The scam begins with deceptive ads posted on social media that claim the wagering sites are working in partnership with popular athletes or social media personalities. The ads invariably state that by using a supplied “promo code,” interested players can claim a $2,500 credit on the advertised gaming website.

The gaming sites ask visitors to create a free account to claim their $2,500 credit, which they can use to play any number of extremely polished video games that ask users to bet on each action. However, when users try to cash out any “winnings” the gaming site will reject the request and prompt the user to make a “verification deposit” of cryptocurrency — typically around $100 — before any money can be distributed.

Those who deposit cryptocurrency funds are soon pressed into more wagering and making additional deposits. And — shocker alert — all players eventually lose everything they’ve invested in the platform.

The number of scam gambling or “scambling” sites has skyrocketed in the past month, and now we know why: The sites all pull their gaming content and detailed strategies for fleecing players straight from the playbook created by Gambler Panel, a Russian-language affiliate program that promises affiliates up to 70 percent of the profits.

Gambler Panel’s website gambler-panel[.]com links to a helpful wiki that explains the scam from cradle to grave, offering affiliates advice on how best to entice visitors, keep them gambling, and extract maximum profits from each victim.

“We have a completely self-written from scratch FAKE CASINO engine that has no competitors,” Gambler Panel’s wiki enthuses. “Carefully thought-out casino design in every pixel, a lot of audits, surveys of real people and test traffic floods were conducted, which allowed us to create something that has no doubts about the legitimacy and trustworthiness even for an inveterate gambling addict with many years of experience.”

Gambler Panel explains that the one and only goal of affiliates is to drive traffic to these scambling sites by any and all means possible.

A machine-translated portion of Gambler Panel’s singular instruction for affiliates: Drive traffic to these scambling sites by any means available.

“Unlike white gambling affiliates, we accept absolutely any type of traffic, regardless of origin, the only limitation is the CIS countries,” the wiki continued, referring to a common prohibition against scamming people in Russia and former Soviet republics in the Commonwealth of Independent States.

The program’s website claims it has more than 20,000 affiliates, who earn a minimum of $10 for each verification deposit. Interested new affiliates must first get approval from the group’s Telegram channel, which currently has around 2,500 active users.

The Gambler Panel channel is replete with images of affiliate panels showing the daily revenue of top affiliates, scantily-clad young women promoting the Gambler logo, and fast cars that top affiliates claimed they bought with their earnings.

A machine-translated version of the wiki for the affiliate program Gambler Panel.

The apparent popularity of this scambling niche is a consequence of the program’s ease of use and detailed instructions for successfully reproducing virtually every facet of the scam. Indeed, much of the tutorial focuses on advice and ready-made templates to help even novice affiliates drive traffic via social media websites, particularly on Instagram and TikTok.

Gambler Panel also walks affiliates through a range of possible responses to questions from users who are trying to withdraw funds from the platform. This section, titled “Rules for working in Live chat,” urges scammers to respond quickly to user requests (1-7 minutes), and includes numerous strategies for keeping the conversation professional and the user on the platform as long as possible.

A machine-translated version of the Gambler Panel’s instructions on managing chat support conversations with users.

The connection between Gambler Panel and the explosion in the number of scambling websites was made by a 17-year-old developer who operates multiple Discord servers that have been flooded lately with misleading ads for these sites.

The researcher, who asked to be identified only by the nickname “Thereallo,” said Gambler Panel has built a scalable business product for other criminals.

“The wiki is kinda like a ‘how to scam 101’ for criminals written with the clarity you would expect from a legitimate company,” Thereallo said. “It’s clean, has step by step guides, and treats their scam platform like a real product. You could swap out the content, and it could be any documentation for startups.”

“They’ve minimized their own risk — spreading the links on Discord / Facebook / YT Shorts, etc. — and outsourced it to a hungry affiliate network, just like a franchise,” Thereallo wrote in response to questions.

“A centralized platform that can serve over 1,200 domains with a shared user base, IP tracking, and a custom API is not at all a trivial thing to build,” Thereallo said. “It’s a scalable system designed to be a resilient foundation for thousands of disposable scam sites.”

The security firm Silent Push has compiled a list of the latest domains associated with the Gambler Panel, available here (.csv).

Cybercriminal groups peddling sophisticated phishing kits that convert stolen card data into mobile wallets have recently shifted their focus to targeting customers of brokerage services, new research shows. Undeterred by security controls at these trading platforms that block users from wiring funds directly out of accounts, the phishers have pivoted to using multiple compromised brokerage accounts in unison to manipulate the prices of foreign stocks.

Image: Shutterstock, WhataWin.

This so-called ‘ramp and dump‘ scheme borrows its name from age-old “pump and dump” scams, wherein fraudsters purchase a large number of shares in some penny stock, and then promote the company in a frenzied social media blitz to build up interest from other investors. The fraudsters dump their shares after the price of the penny stock increases to some degree, which usually then causes a sharp drop in the value of the shares for legitimate investors.

With ramp and dump, the scammers do not need to rely on ginning up interest in the targeted stock on social media. Rather, they will preposition themselves in the stock that they wish to inflate, using compromised accounts to purchase large volumes of it and then dumping the shares after the stock price reaches a certain value. In February 2025, the FBI said it was seeking information from victims of this scheme.

“In this variation, the price manipulation is primarily the result of controlled trading activity conducted by the bad actors behind the scam,” reads an advisory from the Financial Industry Regulatory Authority (FINRA), a private, non-profit organization that regulates member brokerage firms. “Ultimately, the outcome for unsuspecting investors is the same—a catastrophic collapse in share price that leaves investors with unrecoverable losses.”

Ford Merrill is a security researcher at SecAlliance, a CSIS Security Group company. Merrill said he has tracked recent ramp-and-dump activity to a bustling Chinese-language community that is quite openly selling advanced mobile phishing kits on Telegram.

“They will often coordinate with other actors and will wait until a certain time to buy a particular Chinese IPO [initial public offering] stock or penny stock,” said Merrill, who has been chronicling the rapid maturation and growth of the China-based phishing community over the past three years.

“They’ll use all these victim brokerage accounts, and if needed they’ll liquidate the account’s current positions, and will preposition themselves in that instrument in some account they control, and then sell everything when the price goes up,” he said. “The victim will be left with worthless shares of that equity in their account, and the brokerage may not be happy either.”

Merrill said the early days of these phishing groups — between 2022 and 2024 — were typified by phishing kits that used text messages to spoof the U.S. Postal Service or some local toll road operator, warning about a delinquent shipping or toll fee that needed paying. Recipients who clicked the link and provided their payment information at a fake USPS or toll operator site were then asked to verify the transaction by sharing a one-time code sent via text message.

In reality, the victim’s bank is sending that code to the mobile number on file for their customer because the fraudsters have just attempted to enroll that victim’s card details into a mobile wallet. If the visitor supplies that one-time code, their payment card is then added to a new mobile wallet on an Apple or Google device that is physically controlled by the phishers.

The phishing gangs typically load multiple stolen cards to digital wallets on a single Apple or Android device, and then sell those phones in bulk to scammers who use them for fraudulent e-commerce and tap-to-pay transactions.

An image from the Telegram channel for a popular Chinese mobile phishing kit vendor shows 10 mobile phones for sale, each loaded with 4-6 digital wallets from different financial institutions.

This China-based phishing collective exposed a major weakness common to many U.S.-based financial institutions that already require multi-factor authentication: The reliance on a single, phishable one-time token for provisioning mobile wallets. Happily, Merrill said many financial institutions that were caught flat-footed on this scam two years ago have since strengthened authentication requirements for onboarding new mobile wallets (such as requiring the card to be enrolled via the bank’s mobile app).

But just as squeezing one part of a balloon merely forces the air trapped inside to bulge into another area, fraudsters don’t go away when you make their current enterprise less profitable: They just shift their focus to a less-guarded area. And lately, that gaze has settled squarely on customers of the major brokerage platforms, Merrill said.

THE OUTSIDER

Merrill pointed to several Telegram channels operated by some of the more accomplished phishing kit sellers, which are full of videos demonstrating how every feature in their kits can be tailored to the attacker’s target. The video snippet below comes from the Telegram channel of “Outsider,” a popular Mandarin-speaking phishing kit vendor whose latest offering includes a number of ready-made templates for using text messages to phish brokerage account credentials and one-time codes.

According to Merrill, Outsider is a woman who previously went by the handle “Chenlun.” KrebsOnSecurity profiled Chenlun’s phishing empire in an October 2023 story about a China-based group that was phishing mobile customers of more than a dozen postal services around the globe. In that case, the phishing sites were using a Telegram bot that sent stolen credentials to the “@chenlun” Telegram account.

Chenlun’s phishing lures are sent via Apple’s iMessage and Google’s RCS service and spoof one of the major brokerage platforms, warning that the account has been suspended for suspicious activity and that recipients should log in and verify some information. The missives include a link to a phishing page that collects the customer’s username and password, and then asks the user to enter a one-time code that will arrive via SMS.

The new phish kit videos on Outsider’s Telegram channel only feature templates for Schwab customers, but Merrill said the kit can easily be adapted to target other brokerage platforms. One reason the fraudsters are picking on brokerage firms, he said, has to do with the way they handle multi-factor authentication.

Schwab clients are presented with two options for second factor authentication when they open an account. Users who select the option to only prompt for a code on untrusted devices can choose to receive it via text message, an automated inbound phone call, or an outbound call to Schwab. With the “always at login” option selected, users can choose to receive the code through the Schwab app, a text message, or a Symantec VIP mobile app.

In response to questions, Schwab said it regularly updates clients on emerging fraud trends, including this specific type, which the company addressed in communications sent to clients earlier this year.

The 2FA text message from Schwab warns recipients against giving away their one-time code.

“That message focused on trading-related fraud, highlighting both account intrusions and scams conducted through social media or messaging apps that deceive individuals into executing trades themselves,” Schwab said in a written statement. “We are aware and tracking this trend across several channels, as well as others like it, which attempt to exploit SMS-based verification with stolen credentials. We actively monitor for suspicious patterns and take steps to disrupt them. This activity is part of a broader, industry-wide threat, and we take a multi-layered approach to address and mitigate it.”

Other popular brokerage platforms allow similar methods for multi-factor authentication. Fidelity requires a username and password on initial login, and offers the ability to receive a one-time token via SMS, an automated phone call, or by approving a push notification sent through the Fidelity mobile app. However, all three of these methods for sending one-time tokens are phishable; even with the brokerage firm’s app, the phishers could prompt the user to approve a login request that they initiated in the app with the phished credentials.

Vanguard offers customers a range of multi-factor authentication choices, including the option to require a physical security key in addition to one’s credentials on each login. A security key implements a robust form of multi-factor authentication known as Universal 2nd Factor (U2F), which allows the user to complete the login process simply by connecting an enrolled USB or Bluetooth device and pressing a button. The key works without the need for any special software drivers, and the nice thing about it is your second factor cannot be phished.

THE PERFECT CRIME?

Merrill said that in many ways the ramp-and-dump scheme is the perfect crime because it leaves precious few connections between the victim brokerage accounts and the fraudsters.

“It’s really genius because it decouples so many things,” he said. “They can buy shares [in the stock to be pumped] in their personal account on the Chinese exchanges, and the price happens to go up. The Chinese or Hong Kong brokerages aren’t going to see anything funky.”

Merrill said it’s unclear exactly how those perpetrating these ramp-and-dump schemes coordinate their activities, such as whether the accounts are phished well in advance or shortly before being used to inflate the stock price of Chinese companies. The latter possibility would fit nicely with the existing human infrastructure these criminal groups already have in place.

For example, KrebsOnSecurity recently wrote about research from Merrill and other researchers showing the phishers behind these slick mobile phishing kits employed people to sit for hours at a time in front of large banks of mobile phones being used to send the text message lures. These technicians were needed to respond in real time to victims who were supplying the one-time code sent from their financial institution.

The ashtray says: You’ve been phishing all night.

“You can get access to a victim’s brokerage with a one-time passcode, but then you sort of have to use it right away if you can’t set new security settings so you can come back to that account later,” Merrill said.

The rapid pace of innovations produced by these China-based phishing vendors is due in part to their use of artificial intelligence and large language models to help develop the mobile phishing kits, he added.

“These guys are vibe coding stuff together and using LLMs to translate things or help put the user interface together,” Merrill said. “It’s only a matter of time before they start to integrate the LLMs into their development cycle to make it more rapid. The technologies they are building definitely have helped lower the barrier of entry for everyone.”

Microsoft today released updates to fix more than 100 security flaws in its Windows operating systems and other software. At least 13 of the bugs received Microsoft’s most-dire “critical” rating, meaning they could be abused by malware or malcontents to gain remote access to a Windows system with little or no help from users.

August’s patch batch from Redmond includes an update for CVE-2025-53786, a vulnerability that allows an attacker to pivot from a compromised Microsoft Exchange Server directly into an organization’s cloud environment, potentially gaining control over Exchange Online and other connected Microsoft Office 365 services. Microsoft first warned about this bug on Aug. 6, saying it affects Exchange Server 2016 and Exchange Server 2019, as well as its flagship Exchange Server Subscription Edition.

Ben McCarthy, lead cyber security engineer at Immersive, said a rough search reveals approximately 29,000 Exchange servers publicly facing on the internet that are vulnerable to this issue, with many of them likely to have even older vulnerabilities.

McCarthy said the fix for CVE-2025-53786 requires more than just installing a patch, such as following Microsoft’s manual instructions for creating a dedicated service to oversee and lock down the hybrid connection.

“In effect, this vulnerability turns a significant on-premise Exchange breach into a full-blown, difficult-to-detect cloud compromise with effectively living off the land techniques which are always harder to detect for defensive teams,” McCarthy said.

CVE-2025-53779 is a weakness in the Windows Kerberos authentication system that allows an unauthenticated attacker to gain domain administrator privileges. Microsoft credits the discovery of the flaw to Akamai researcher Yuval Gordon, who dubbed it “BadSuccessor” in a May 2025 blog post. The attack exploits a weakness in “delegated Managed Service Account” or dMSA — a feature that was introduced in Windows Server 2025.

Some of the critical flaws addressed this month with the highest severity (between 9.0 and 9.9 CVSS scores) include a remote code execution bug in the Windows GDI+ component that handles graphics rendering (CVE-2025-53766) and CVE-2025-50165, another graphics rendering weakness. Another critical patch involves CVE-2025-53733, a vulnerability in Microsoft Word that can be exploited without user interaction and triggered through the Preview Pane.

One final critical bug tackled this month deserves attention: CVE-2025-53778, a bug in Windows NTLM, a core function of how Windows systems handle network authentication. According to Microsoft, the flaw could allow an attacker with low-level network access and basic user privileges to exploit NTLM and elevate to SYSTEM-level access — the highest level of privilege in Windows. Microsoft rates the exploitation of this bug as “more likely,” although there is no evidence the vulnerability is being exploited at the moment.

Feel free to holler in the comments if you experience problems installing any of these updates. As ever, the SANS Internet Storm Center has its useful breakdown of the Microsoft patches indexed by severity and CVSS score, and AskWoody.com is keeping an eye out for Windows patches that may cause problems for enterprises and end users.

GOOD MIGRATIONS

Windows 10 users out there likely have noticed by now that Microsoft really wants you to upgrade to Windows 11. The reason is that after the Patch Tuesday on October 14, 2025, Microsoft will stop shipping free security updates for Windows 10 computers. The trouble is, many PCs running Windows 10 do not meet the hardware specifications required to install Windows 11 (or they do, but just barely).

If the experience with Windows XP is any indicator, many of these older computers will wind up in landfills or else will be left running in an unpatched state. But if your Windows 10 PC doesn’t have the hardware chops to run Windows 11 and you’d still like to get some use out of it safely, consider installing a newbie-friendly version of Linux, like Linux Mint.

Like most modern Linux versions, Mint will run on anything with a 64-bit CPU that has at least 2GB of memory, although 4GB is recommended. In other words, it will run on almost any computer produced in the last decade.

There are many versions of Linux available, but Linux Mint is likely to be the most intuitive interface for regular Windows users, and it is largely configurable without any fuss at the text-only command-line prompt. Mint and other flavors of Linux come with LibreOffice, which is an open source suite of tools that includes applications similar to Microsoft Office, and it can open, edit and save documents as Microsoft Office files.

If you’d prefer to give Linux a test drive before installing it on a Windows PC, you can always just download it to a removable USB drive. From there, reboot the computer (with the removable drive plugged in) and select the option at startup to run the operating system from the external USB drive. If you don’t see an option for that after restarting, try restarting again and hitting the F8 button, which should open a list of bootable drives. Here’s a fairly thorough tutorial that walks through exactly how to do all this.

And if this is your first time trying out Linux, relax and have fun: The nice thing about a “live” version of Linux (as it’s called when the operating system is run from a removable drive such as a CD or a USB stick) is that none of your changes persist after a reboot. Even if you somehow manage to break something, a restart will return the system back to its original state.

On July 22, 2025, the European police agency Europol said a long-running investigation led by the French Police resulted in the arrest of a 38-year-old administrator of XSS, a Russian-language cybercrime forum with more than 50,000 members. The action has triggered an ongoing frenzy of speculation and panic among XSS denizens about the identity of the unnamed suspect, but the consensus is that he is a pivotal figure in the crime forum scene who goes by the hacker handle “Toha.” Here’s a deep dive on what’s knowable about Toha, and a short stab at who got nabbed.

An unnamed 38-year-old man was arrested in Kiev last month on suspicion of administering the cybercrime forum XSS. Image: ssu.gov.ua.

Europol did not name the accused, but published partially obscured photos of him from the raid on his residence in Kiev. The police agency said the suspect acted as a trusted third party — arbitrating disputes between criminals — and guaranteeing the security of transactions on XSS. A statement from Ukraine’s SBU security service said XSS counted among its members many cybercriminals from various ransomware groups, including REvil, LockBit, Conti, and Qiliin.

Since the Europol announcement, the XSS forum resurfaced at a new address on the deep web (reachable only via the anonymity network Tor). But from reviewing the recent posts, there appears to be little consensus among longtime members about the identity of the now-detained XSS administrator.

The most frequent comment regarding the arrest was a message of solidarity and support for Toha, the handle chosen by the longtime administrator of XSS and several other major Russian forums. Toha’s accounts on other forums have been silent since the raid.

Europol said the suspect has enjoyed a nearly 20-year career in cybercrime, which roughly lines up with Toha’s history. In 2005, Toha was a founding member of the Russian-speaking forum Hack-All. That is, until it got massively hacked a few months after its debut. In 2006, Toha rebranded the forum to exploit[.]in, which would go on to draw tens of thousands of members, including an eventual Who’s-Who of wanted cybercriminals.

Toha announced in 2018 that he was selling the Exploit forum, prompting rampant speculation on the forums that the buyer was secretly a Russian or Ukrainian government entity or front person. However, those suspicions were unsupported by evidence, and Toha vehemently denied the forum had been given over to authorities.

One of the oldest Russian-language cybercrime forums was DaMaGeLaB, which operated from 2004 to 2017, when its administrator “Ar3s” was arrested. In 2018, a partial backup of the DaMaGeLaB forum was reincarnated as xss[.]is, with Toha as its stated administrator.

CROSS-SITE GRIFTING

Clues about Toha’s early presence on the Internet — from ~2004 to 2010 — are available in the archives of Intel 471, a cyber intelligence firm that tracks forum activity. Intel 471 shows Toha used the same email address across multiple forum accounts, including at Exploit, Antichat, Carder[.]su and inattack[.]ru.

DomainTools.com finds Toha’s email address — toschka2003@yandex.ru — was used to register at least a dozen domain names — most of them from the mid- to late 2000s. Apart from exploit[.]in and a domain called ixyq[.]com, the other domains registered to that email address end in .ua, the top-level domain for Ukraine (e.g. deleted.org[.]ua, lj.com[.]ua, and blogspot.org[.]ua).

A 2008 snapshot of a domain registered to toschka2003@yandex.ru and to Anton Medvedovsky in Kiev. Note the message at the bottom left, “Protected by Exploit,in.” Image: archive.org.

Nearly all of the domains registered to toschka2003@yandex.ru contain the name Anton Medvedovskiy in the registration records, except for the aforementioned ixyq[.]com, which is registered to the name Yuriy Avdeev in Moscow.

This Avdeev surname came up in a lengthy conversation with Lockbitsupp, the leader of the rapacious and destructive ransomware affiliate group Lockbit. The conversation took place in February 2024, when Lockbitsupp asked for help identifying Toha’s real-life identity.

In early 2024, the leader of the Lockbit ransomware group — Lockbitsupp — asked for help investigating the identity of the XSS administrator Toha, which he claimed was a Russian man named Anton Avdeev.

Lockbitsupp didn’t share why he wanted Toha’s details, but he maintained that Toha’s real name was Anton Avdeev. I declined to help Lockbitsupp in whatever revenge he was planning on Toha, but his question made me curious to look deeper.

It appears Lockbitsupp’s query was based on a now-deleted Twitter post from 2022, when a user by the name “3xp0rt” asserted that Toha was a Russian man named Anton Viktorovich Avdeev, born October 27, 1983.

Searching the web for Toha’s email address toschka2003@yandex.ru reveals a 2010 sales thread on the forum bmwclub.ru where a user named Honeypo was selling a 2007 BMW X5. The ad listed the contact person as Anton Avdeev and gave the contact phone number 9588693.

A search on the phone number 9588693 in the breach tracking service Constella Intelligence finds plenty of official Russian government records with this number, date of birth and the name Anton Viktorovich Avdeev. For example, hacked Russian government records show this person has a Russian tax ID and SIN (Social Security number), and that they were flagged for traffic violations on several occasions by Moscow police; in 2004, 2006, 2009, and 2014.

Astute readers may have noticed by now that the ages of Mr. Avdeev (41) and the XSS admin arrested this month (38) are a bit off. This would seem to suggest that the person arrested is someone other than Mr. Avdeev, who did not respond to requests for comment.

A FLY ON THE WALL

For further insight on this question, KrebsOnSecurity sought comments from Sergeii Vovnenko, a former cybercriminal from Ukraine who now works at the security startup paranoidlab.com. I reached out to Vovnenko because for several years beginning around 2010 he was the owner and operator of thesecure[.]biz, an encrypted “Jabber” instant messaging server that Europol said was operated by the suspect arrested in Kiev. Thesecure[.]biz grew quite popular among many of the top Russian-speaking cybercriminals because it scrupulously kept few records of its users’ activity, and its administrator was always a trusted member of the community.

The reason I know this historic tidbit is that in 2013, Vovnenko — using the hacker nicknames “Fly,” and “Flycracker” — hatched a plan to have a gram of heroin purchased off of the Silk Road darknet market and shipped to our home in Northern Virginia. The scheme was to spoof a call from one of our neighbors to the local police, saying this guy Krebs down the street was a druggie who was having narcotics delivered to his home.

I happened to be lurking on Flycracker’s private cybercrime forum when his heroin-framing plan was carried out, and called the police myself before the smack eventually arrived in the U.S. Mail. Vovnenko was later arrested for unrelated cybercrime activities, extradited to the United States, convicted, and deported after a 16-month stay in the U.S. prison system [on several occasions, he has expressed heartfelt apologies for the incident, and we have since buried the hatchet].

Vovnenko said he purchased a device for cloning credit cards from Toha in 2009, and that Toha shipped the item from Russia. Vovnenko explained that he (Flycracker) was the owner and operator of thesecure[.]biz from 2010 until his arrest in 2014.

Vovnenko believes thesecure[.]biz was stolen while he was in jail, either by Toha and/or an XSS administrator who went by the nicknames N0klos and Sonic.

“When I was in jail, [the] admin of xss.is stole that domain, or probably N0klos bought XSS from Toha or vice versa,” Vovnenko said of the Jabber domain. “Nobody from [the forums] spoke with me after my jailtime, so I can only guess what really happened.”

N0klos was the owner and administrator of an early Russian-language cybercrime forum known as Darklife[.]ws. However, N0kl0s also appears to be a lifelong Russian resident, and in any case seems to have vanished from Russian cybercrime forums several years ago.

Asked whether he believes Toha was the XSS administrator who was arrested this month in Ukraine, Vovnenko maintained that Toha is Russian, and that “the French cops took the wrong guy.”

WHO IS TOHA?

So who did the Ukrainian police arrest in response to the investigation by the French authorities? It seems plausible that the BMW ad invoking Toha’s email address and the name and phone number of a Russian citizen was simply misdirection on Toha’s part — intended to confuse and throw off investigators. Perhaps this even explains the Avdeev surname surfacing in the registration records from one of Toha’s domains.

But sometimes the simplest answer is the correct one. “Toha” is a common Slavic nickname for someone with the first name “Anton,” and that matches the name in the registration records for more than a dozen domains tied to Toha’s toschka2003@yandex.ru email address: Anton Medvedovskiy.

Constella Intelligence finds there is an Anton Gannadievich Medvedovskiy living in Kiev who will be 38 years old in December. This individual owns the email address itsmail@i.ua, as well an an Airbnb account featuring a profile photo of a man with roughly the same hairline as the suspect in the blurred photos released by the Ukrainian police. Mr. Medvedovskiy did not respond to a request for comment.

My take on the takedown is that the Ukrainian authorities likely arrested Medvedovskiy. Toha shared on DaMaGeLab in 2005 that he had recently finished the 11th grade and was studying at a university — a time when Mevedovskiy would have been around 18 years old. On Dec. 11, 2006, fellow Exploit members wished Toha a happy birthday. Records exposed in a 2022 hack at the Ukrainian public services portal diia.gov.ua show that Mr. Medvedovskiy’s birthday is Dec. 11, 1987.

The law enforcement action and resulting confusion about the identity of the detained has thrown the Russian cybercrime forum scene into disarray in recent weeks, with lengthy and heated arguments about XSS’s future spooling out across the forums.

XSS relaunched on a new Tor address shortly after the authorities plastered their seizure notice on the forum’s  homepage, but all of the trusted moderators from the old forum were dismissed without explanation. Existing members saw their forum account balances drop to zero, and were asked to plunk down a deposit to register at the new forum. The new XSS “admin” said they were in contact with the previous owners and that the changes were to help rebuild security and trust within the community.

However, the new admin’s assurances appear to have done little to assuage the worst fears of the forum’s erstwhile members, most of whom seem to be keeping their distance from the relaunched site for now.

Indeed, if there is one common understanding amid all of these discussions about the seizure of XSS, it is that Ukrainian and French authorities now have several years worth of private messages between XSS forum users, as well as contact rosters and other user data linked to the seized Jabber server.

“The myth of the ‘trusted person’ is shattered,” the user “GordonBellford” cautioned on Aug. 3 in an Exploit forum thread about the XSS admin arrest. “The forum is run by strangers. They got everything. Two years of Jabber server logs. Full backup and forum database.”

GordonBellford continued:

And the scariest thing is: this data array is not just an archive. It is material for analysis that has ALREADY BEEN DONE . With the help of modern tools, they see everything:

Graphs of your contacts and activity.
Relationships between nicknames, emails, password hashes and Jabber ID.
Timestamps, IP addresses and digital fingerprints.
Your unique writing style, phraseology, punctuation, consistency of grammatical errors, and even typical typos that will link your accounts on different platforms.

They are not looking for a needle in a haystack. They simply sifted the haystack through the AI sieve and got ready-made dossiers.

On Sunday, July 20, Microsoft Corp. issued an emergency security update for a vulnerability in SharePoint Server that is actively being exploited to compromise vulnerable organizations. The patch comes amid reports that malicious hackers have used the SharePoint flaw to breach U.S. federal and state agencies, universities, and energy companies.

Image: Shutterstock, by Ascannio.

In an advisory about the SharePoint security hole, a.k.a. CVE-2025-53770, Microsoft said it is aware of active attacks targeting on-premises SharePoint Server customers and exploiting vulnerabilities that were only partially addressed by the July 8, 2025 security update.

The Cybersecurity & Infrastructure Security Agency (CISA) concurred, saying CVE-2025-53770 is a variant on a flaw Microsoft patched earlier this month (CVE-2025-49706). Microsoft notes the weakness applies only to SharePoint Servers that organizations use in-house, and that SharePoint Online and Microsoft 365 are not affected.

The Washington Post reported on Sunday that the U.S. government and partners in Canada and Australia are investigating the hack of SharePoint servers, which provide a platform for sharing and managing documents. The Post reports at least two U.S. federal agencies have seen their servers breached via the SharePoint vulnerability.

According to CISA, attackers exploiting the newly-discovered flaw are retrofitting compromised servers with a backdoor dubbed “ToolShell” that provides unauthenticated, remote access to systems. CISA said ToolShell enables attackers to fully access SharePoint content — including file systems and internal configurations — and execute code over the network.

Researchers at Eye Security said they first spotted large-scale exploitation of the SharePoint flaw on July 18, 2025, and soon found dozens of separate servers compromised by the bug and infected with ToolShell. In a blog post, the researchers said the attacks sought to steal SharePoint server ASP.NET machine keys.

“These keys can be used to facilitate further attacks, even at a later date,” Eye Security warned. “It is critical that affected servers rotate SharePoint server ASP.NET machine keys and restart IIS on all SharePoint servers. Patching alone is not enough. We strongly advise defenders not to wait for a vendor fix before taking action. This threat is already operational and spreading rapidly.”

Microsoft’s advisory says the company has issued updates for SharePoint Server Subscription Edition and SharePoint Server 2019, but that it is still working on updates for supported versions of SharePoint 2019 and SharePoint 2016.

CISA advises vulnerable organizations to enable the anti-malware scan interface (AMSI) in SharePoint, to deploy Microsoft Defender AV on all SharePoint servers, and to disconnect affected products from the public-facing Internet until an official patch is available.

The security firm Rapid7 notes that Microsoft has described CVE-2025-53770 as related to a previous vulnerability — CVE-2025-49704, patched earlier this month — and that CVE-2025-49704 was part of an exploit chain demonstrated at the Pwn2Own hacking competition in May 2025. That exploit chain invoked a second SharePoint weakness — CVE-2025-49706 — which Microsoft unsuccessfully tried to fix in this month’s Patch Tuesday.

Microsoft also has issued a patch for a related SharePoint vulnerability — CVE-2025-53771; Microsoft says there are no signs of active attacks on CVE-2025-53771, and that the patch is to provide more robust protections than the update for CVE-2025-49706.

This is a rapidly developing story. Any updates will be noted with timestamps.

Marko Elez, a 25-year-old employee at Elon Musk’s Department of Government Efficiency (DOGE), has been granted access to sensitive databases at the U.S. Social Security Administration, the Treasury and Justice departments, and the Department of Homeland Security. So it should fill all Americans with a deep sense of confidence to learn that Mr. Elez over the weekend inadvertently published a private key that allowed anyone to interact directly with more than four dozen large language models (LLMs) developed by Musk’s artificial intelligence company xAI.

Image: Shutterstock, @sdx15.

On July 13, Mr. Elez committed a code script to GitHub called “agent.py” that included a private application programming interface (API) key for xAI. The inclusion of the private key was first flagged by GitGuardian, a company that specializes in detecting and remediating exposed secrets in public and proprietary environments. GitGuardian’s systems constantly scan GitHub and other code repositories for exposed API keys, and fire off automated alerts to affected users.

Philippe Caturegli, “chief hacking officer” at the security consultancy Seralys, said the exposed API key allowed access to at least 52 different LLMs used by xAI. The most recent LLM in the list was called “grok-4-0709” and was created on July 9, 2025.

Grok, the generative AI chatbot developed by xAI and integrated into Twitter/X, relies on these and other LLMs (a query to Grok before publication shows Grok currently uses Grok-3, which was launched in Feburary 2025). Earlier today, xAI announced that the Department of Defense will begin using Grok as part of a contract worth up to $200 million. The contract award came less than a week after Grok began spewing antisemitic rants and invoking Adolf Hitler.

Mr. Elez did not respond to a request for comment. The code repository containing the private xAI key was removed shortly after Caturegli notified Elez via email. However, Caturegli said the exposed API key still works and has not yet been revoked.

“If a developer can’t keep an API key private, it raises questions about how they’re handling far more sensitive government information behind closed doors,” Caturegli told KrebsOnSecurity.

Prior to joining DOGE, Marko Elez worked for a number of Musk’s companies. His DOGE career began at the Department of the Treasury, and a legal battle over DOGE’s access to Treasury databases showed Elez was sending unencrypted personal information in violation of the agency’s policies.

While still at Treasury, Elez resigned after The Wall Street Journal linked him to social media posts that advocated racism and eugenics. When Vice President J.D. Vance lobbied for Elez to be rehired, President Trump agreed and Musk reinstated him.

Since his re-hiring as a DOGE employee, Elez has been granted access to databases at one federal agency after another. TechCrunch reported in February 2025 that he was working at the Social Security Administration. In March, Business Insider found Elez was part of a DOGE detachment assigned to the Department of Labor.

Marko Elez, in a photo from a social media profile.

In April, The New York Times reported that Elez held positions at the U.S. Customs and Border Protection and the Immigration and Customs Enforcement (ICE) bureaus, as well as the Department of Homeland Security. The Washington Post later reported that Elez, while serving as a DOGE advisor at the Department of Justice, had gained access to the Executive Office for Immigration Review’s Courts and Appeals System (EACS).

Elez is not the first DOGE worker to publish internal API keys for xAI: In May, KrebsOnSecurity detailed how another DOGE employee leaked a private xAI key on GitHub for two months, exposing LLMs that were custom made for working with internal data from Musk’s companies, including SpaceX, Tesla and Twitter/X.

Caturegli said it’s difficult to trust someone with access to confidential government systems when they can’t even manage the basics of operational security.

“One leak is a mistake,” he said. “But when the same type of sensitive key gets exposed again and again, it’s not just bad luck, it’s a sign of deeper negligence and a broken security culture.”

Since 2024, Microsoft Threat Intelligence has observed remote information technology (IT) workers deployed by North Korea leveraging AI to improve the scale and sophistication of their operations, steal data, and generate revenue for the Democratic People’s Republic of Korea (DPRK). Among the changes noted in the North Korean remote IT worker tactics, techniques, and procedures (TTPs) include the use of AI tools to replace images in stolen employment and identity documents and enhance North Korean IT worker photos to make them appear more professional. We’ve also observed that they’ve been utilizing voice-changing software.

North Korea has deployed thousands of remote IT workers to assume jobs in software and web development as part of a revenue generation scheme for the North Korean government. These highly skilled workers are most often located in North Korea, China, and Russia, and use tools such as virtual private networks (VPNs) and remote monitoring and management (RMM) tools together with witting accomplices to conceal their locations and identities.

Historically, North Korea’s fraudulent remote worker scheme has focused on targeting United States (US) companies in the technology, critical manufacturing, and transportation sectors. However, we’ve observed North Korean remote workers evolving to broaden their scope to target various industries globally that offer technology-related roles. Since 2020, the US government and cybersecurity community have identified thousands of North Korean workers infiltrating companies across various industries.

Organizations can protect themselves from this threat by implementing stricter pre-employment vetting measures and creating policies to block unapproved IT management tools. For example, when evaluating potential employees, employers and recruiters should ensure that the candidates’ social media and professional accounts are unique and verify their contact information and digital footprint. Organizations should also be particularly cautious with staffing company employees, check for consistency in resumes, and use video calls to confirm a worker’s identity.

Microsoft Threat Intelligence tracks North Korean IT remote worker activity as Jasper Sleet (formerly known as Storm-0287). We also track several other North Korean activity clusters that pursue fraudulent employment using similar techniques and tools, including Storm-1877 and Moonstone Sleet. To disrupt this activity and protect our customers, we’ve suspended 3,000 known Microsoft consumer accounts (Outlook/Hotmail) created by North Korean IT workers. We have also implemented several detections to alert our customers of this activity through Microsoft Entra ID Protection and Microsoft Defender XDR as noted at the end of this blog. As with any observed nation-state threat actor activity, Microsoft has directly notified targeted or compromised customers, providing them with important information needed to secure their environments. As we continue to observe more attempts by threat actors to leverage AI, not only do we report on them, but we also have principles in place to take action against them.

This blog provides additional information on the North Korean remote IT worker operations we published previously, including Jasper Sleet’s usual TTPs to secure employment, such as using fraudulent identities and facilitators. We also provide recent observations regarding their use of AI tools. Finally, we share detailed guidance on how to investigate, monitor, and remediate possible North Korean remote IT worker activity, as well as detections and hunting capabilities to surface this threat.

From North Korea to the world: The remote IT workforce

Since at least early 2020, Microsoft has tracked a global operation conducted by North Korea in which skilled IT workers apply for remote job opportunities to generate revenue and support state interests. These workers present themselves as foreign (non-North Korean) or domestic-based teleworkers and use a variety of fraudulent means to bypass employment verification controls.

North Korea’s fraudulent remote worker scheme has since evolved, establishing itself as a well-developed operation that has allowed North Korean remote workers to infiltrate technology-related roles across various industries. In some cases, victim organizations have even reported that remote IT workers were some of their most talented employees. Historically, this operation has focused on applying for IT, software development, and administrator positions in the technology sector. Such positions provide North Korean threat actors access to highly sensitive information to conduct information theft and extortion, among other operations.

North Korean IT workers are a multifaceted threat because not only do they generate revenue for the North Korean regime, which violates international sanctions, they also use their access to steal sensitive intellectual property, source code, or trade secrets. In some cases, these North Korean workers even extort their employer into paying them in exchange for not publicly disclosing the company’s data.

Between 2020 and 2022, the US government found that over 300 US companies in multiple industries, including several Fortune 500 companies, had unknowingly employed these workers, indicating the magnitude of this threat. The workers also attempted to gain access to information at two government agencies. Since then, the cybersecurity community has continued to detect thousands of North Korean workers. On January 3, 2025, the Justice Department released an indictment identifying two North Korean nationals and three facilitators responsible for conducting fraudulent work between 2018 and 2024. The indicted individuals generated a revenue of at least US$866,255 from only ten of the at least 64 infiltrated US companies.

North Korean threat actors are evolving across the threat landscape to incorporate more sophisticated tactics and tools to conduct malicious employment-related activity, including the use of custom and AI-enabled software.

Tactics and techniques

The tactics and techniques employed by North Korean remote IT workers involve a sophisticated ecosystem of crafting fake personas, performing remote work, and securing payments. North Korean IT workers apply for remote roles, in various sectors, at organizations across the globe.

They create, rent, or procure stolen identities that match the geo-location of their target organizations (for example, they would establish a US-based identity to apply for roles at US-based companies), create email accounts and social media profiles, and establish legitimacy through fake portfolios and profiles on developer platforms like GitHub and LinkedIn. Additionally, they leverage AI tools to enhance their operations, including image creation and voice-changing software. Facilitators play a crucial role in validating fraudulent identities and managing logistics, such as forwarding company hardware and creating accounts on freelance job websites. To evade detection, these workers use VPNs, virtual private servers (VPSs), and proxy services as well as RMM tools to connect to a device housed at a facilitator’s laptop farm located in the country of the job.

Crafting fake personas and profiles

The North Korean remote IT worker fraud scheme begins with the procurement of identities for the workers. These identities, which can be stolen or “rented” from witting individuals, include names, national identification numbers, and dates of birth. The workers might also leverage services that generate fraudulent identities, complete with seemingly legitimate documentation, to fabricate their personas. They then create email accounts and social media pages they use to apply for jobs, often indirectly through staffing or contracting companies. They also apply for freelance opportunities through freelancer sites as an additional avenue for revenue generation. Notably, they often use the same names/profiles repeatedly rather than creating unique personas for each successful infiltration.

Additionally, the North Korean IT workers have used fake profiles on LinkedIn to communicate with recruiters and apply for jobs.

The workers tailor their fake resumes and profiles to match the requirements for specific remote IT positions, thus increasing their chances of getting selected. Over time, we’ve observed these fake resumes and employee documents noticeably improving in quality, now appearing more polished and lacking grammatical errors facilitated by AI.

Establishing digital footprint

After creating their fake personas, the North Korean IT workers then attempt to establish legitimacy by creating digital footprints for these fake personas. They typically leverage communication, networking, and developer platforms, (for example, GitHub) to showcase their supposed portfolio of previous work samples:

Using AI to improve operations

Microsoft Threat intelligence has observed North Korean remote IT workers leveraging AI to improve the quantity and quality of their operations. For example, in October 2024, we found a public repository containing actual and AI-enhanced images of suspected North Korean IT workers:

The repository also contained the resumes and email accounts used by the said workers, along with the following tools and resources they can use to secure employment and to do their work:

• VPS and VPN accounts, along with specific VPS IP addresses
• Playbooks on conducting identity theft and creating and bidding jobs on freelancer websites
• Wallet information and suspected payments made to facilitators
• LinkedIn, GitHub, Upwork, TeamViewer, Telegram, and Skype accounts
• Tracking sheet of work performed, and payments received by the IT workers

Image creation

Based on our review of the repository mentioned previously, North Korean IT workers appear to conduct identity theft and then use AI tools like Faceswap to move their pictures over to the stolen employment and identity documents. The attackers also use these AI tools to take pictures of the workers and move them to more professional looking settings. The workers then use these AI-generated pictures on one or more resumes or profiles when applying for jobs.

Communications

Microsoft Threat Intelligence has observed that North Korean IT workers are also experimenting with other AI technologies such as voice-changing software. While we haven’t observed threat actors using combined AI voice and video products as a tactic first hand, we do recognize that combining these technologies could allow future threat actor campaigns to trick interviewers into thinking they aren’t communicating with a North Korean IT worker. If successful, this tactic could allow the North Korean IT workers to do interviews directly and no longer rely on facilitators standing in for them on interviews or selling them account access.

Facilitators for initial access

North Korean remote IT workers require assistance from a witting facilitator to help find jobs, pass the employment verification process, and once hired, successfully work remotely. We’ve observed Jasper Sleet advertising job opportunities for facilitator roles under the guise of partnering with a remote job candidate to help secure an IT role in a competitive market:

The IT workers may have the facilitators assist in creating accounts on remote and freelance job websites. They might also ask the facilitator to perform the following tasks as their relationship builds:

• Create a bank account for the North Korean IT worker, or lend their (the facilitator’s) own account to the worker
• Purchase mobile phone numbers or SIM cards

During the employment verification process, the witting accomplice helps the North Korean IT workers validate the latter’s fraudulent identities using online background check service providers. The documents submitted by the workers include fake or stolen drivers’ licenses, social security cards, passports, and permanent resident identification cards. Workers train using interview scripts, which include a justification for why the employee must work remotely.

Once hired, the remote workers direct company laptops and hardware to be sent to the address of the accomplice. The accomplice then either runs a laptop farm that provides the laptops with an internet connection at the geo-location of the role or forwards the items internationally. For hardware that remain in the country of the role, the accomplice signs into the computers and installs software that enables the workers to connect remotely. Remote IT workers might also access devices remotely using IP-based KVM devices, like PiKVM or TinyPilot.

Defense evasion and persistence

To conceal their physical location as well as maintain persistence and blend into the target organization’s environment, the workers typically use VPNs (particularly Astrill VPN), VPSs, proxy services, and RMM tools. Microsoft Threat Intelligence has observed the persistent use of JumpConnect, TinyPilot, Rust Desk, TeamViewer, AnyViewer, and Anydesk. When an in-person presence or face-to-face meeting is required, for example to confirm banking information or attend a meeting, the workers have been known to pay accomplices to stand in for them. When possible, however, the workers eliminate all face-to-face contact, offering fraudulent excuses for why they are not on camera during video teleconferencing calls or speaking.

Attribution

Microsoft Threat Intelligence uses the name Jasper Sleet (formerly known as Storm-0287) to represent activity associated with North Korean’s remote IT worker program. These workers are primarily focused on revenue generation, use remote access tools, and likely fall under a particular leadership structure in North Korea. We also track several other North Korean activity clusters that pursue fraudulent employment using similar techniques and tools, including Storm-1877 and Moonstone Sleet.

How Microsoft disrupts North Korean remote IT worker operations with machine learning

Microsoft has successfully scaled analyst tradecraft to accelerate the identification and disruption of North Korean IT workers in customer environments by developing a custom machine learning solution. This has been achieved by leveraging Microsoft’s existing threat intelligence and weak signals generated by monitoring for many of the red flags listed in this blog, among others. For example, this solution uses impossible time travel risk detections, most commonly between a Western nation and China or Russia. The machine learning workflow uses these features to surface suspect accounts most likely to be North Korean IT workers for assessment by Microsoft Threat Intelligence analysts.

Once Microsoft Threat Intelligence reviews and confirms that an account is indeed associated with a North Korean IT worker, customers are then notified with a Microsoft Entra ID Protection risk detection warning of a risky sign-in based on Microsoft’s threat intelligence. Microsoft Defender XDR customers also receive the alert Sign-in activity by a suspected North Korean entity in the Microsoft Defender portal.

Defending against North Korean remote IT worker infiltration

Defending against the threats from North Korean remote IT workers involves a threefold strategy:

• Ensuring a proper vetting approach is in place for freelance workers and vendors
• Monitoring for anomalous user activity
• Responding to suspected Jasper Sleet signals in close coordination with your insider risk team

Investigate

How can you identify a North Korean remote IT worker in the hiring process?

To protect your organization against a potential North Korean insider threat, it is important for your organization to prioritize a process for verifying employees to identify potential risks. The following can be used to assess potential employees:

• Confirm the potential employee has a digital footprint and look for signs of authenticity. This includes a real phone number (not VoIP), a residential address, and social media accounts. Ensure the potential employee’s social media/professional accounts are not highly similar to the accounts of other individuals. In addition, check that the contact phone number listed on the potential employee’s account is unique and not also used by other accounts.
• Scrutinize resumes and background checks for consistency of names, addresses, and dates. Consider contacting references by phone or video-teleconference rather than email only.
• Exercise greater scrutiny for employees of staffing companies, since this is the easiest avenue for North Korean workers to infiltrate target companies.
• Search whether a potential employee is employed at multiple companies using the same persona.
• Ensure the potential employee is seen on camera during multiple video telecommunication sessions. If the potential employee reports video and/or microphone issues that prohibit participation, this should be considered a red flag.
• During video verification, request individuals to physically hold driver’s licenses, passports, or identity documents up to camera.
• Keep records, including recordings of video interviews, of all interactions with potential employees.
• Require notarized proof of identity.

Monitor

How can your organization prevent falling victim to the North Korean remote IT worker technique?

To prevent the risks associated with North Korean insider threats, it’s vital to monitor for activity typically associated with this fraudulent scheme.

Monitor for identifiable characteristics of North Korean remote workers

Microsoft has identified the following characteristics of a North Korean remote worker. Note that not all the criteria are necessarily required, and further, a positive identification of a remote worker doesn’t guarantee that the worker is North Korean.

• The employee lists a Chinese phone number on social media accounts that is used by other accounts.
• The worker’s work-issued laptop authenticates from an IP address of a known North Korean IT worker laptop farm, or from foreign—most commonly Chinese or Russian—IP addresses even though the worker is supposed to have a different work location.
• The worker is employed at multiple companies using the same persona. Employees of staffing companies require heightened scrutiny, given this is the easiest way for North Korean workers to infiltrate target companies.
• Once a laptop is issued to the worker, RMM software is immediately downloaded onto it and used in combination with a VPN.
• The worker has never been seen on camera during a video telecommunication session or is only seen a few times. The worker may also report video and/or microphone issues that prohibit participation from the start.
• The worker’s online activity doesn’t align with routine co-worker hours, with limited engagement across approved communication platforms.

Monitor for activity associated with Jasper Sleet access

• If RMM tools are used in your environment, enforce security settings where possible, to implement MFA:
  • Use Windows Defender Application Control or AppLocker to create policies to block unapproved IT management tools. Consider hunting for unapproved RMM software installations and creating custom detections (Investigation & response > Hunting > Advanced hunting > Manage rules > Create custom detection) for any advanced hunting queries that are useful indicators of anomalous or unapproved activity in your environment.
  • If an unapproved installation is discovered, reset passwords for accounts used to install the RMM services. If a system-level account was used to install the software, further investigation may be warranted.
• Monitor for impossible travel—for example, a supposedly US-based employee signing in from China or Russia.
• Monitor for use of public VPNs such as Astrill. For example, IP addresses associated with VPNs known to be used by Jasper Sleet can be added to Sentinel watchlists. Or, Microsoft Defender for Identity can integrate with your VPN solution to provide more information about user activity, such as extra detection for abnormal VPN connections.
• Monitor for signals of insider threats in your environment. Microsoft Purview Insider Risk Management can help identify potentially malicious or inadvertent insider risks.
• Monitor for consistent user activity outside of typical working hours.

Remediate

What are the next steps if you positively identify a North Korean remote IT worker employed at your company?

Because Jasper Sleet activity follows legitimate job offers and authorized access, Microsoft recommends approaching confirmed or suspected Jasper Sleet intrusions with an insider risk approach using your organization’s insider risk response plan or incident response provider like Microsoft Incident Response. Some steps might include:

• Restrict response efforts to a small, trusted insider risk working group, trained in operational security (OPSEC) to avoid tipping off subjects and potential collaborators.
• Rapidly evaluate the subject’s proximity to critical assets, such as:
  • Leadership or sensitive teams
  • Direct reports or vendor staff the subject has influence over
  • Suppliers or vendors
  • People/non-people accounts, production/pre-production environments, shared accounts, security groups, third-party accounts, security groups, distribution groups, data clusters, and more
• Conduct preliminary link analysis to:
  • Detect relationships with potential collaborators, supporters, or other potential aliases operated by the same actor
  • Identify shared indicators (for example, shared IP addresses, behavioral overlap)
  • Avoid premature action that might alert other Jasper Sleet operators
• Conduct a risk-based prioritization of efforts, informed by:
  • Placement and access to critical assets (not necessarily where you identified them)Stakeholder insight from potentially impacted business units
  • Business impact considerations of containment (which might support additional collection/analysis) or mitigation (for example, eviction)
• Conduct open-source intelligence (OSINT) collection and analysis to:
  • Determine if the identity associated with the threat actor is associated with a real person. For example, North Korean IT workers have leveraged stolen identities of real US persons to facilitate their fraud. Conduct OSINT on all available personally identifiable information (PII) provided by the actor (name, date of birth, SSN, home of record, phone number, emergency contact, and others) and determine if these items are linked to additional North Korean actors, and/or real persons’ identities.
  • Gather all known external accounts operated by the alias/persona (for example, LinkedIn, GitHub, freelance working sites, bug bounty programs).
  • Perform analysis on account images using open-source tools such as FaceForensics++ to determine prevalence of AI-generated content. Detection opportunities within video and imagery include: 
    • Temporal consistency issues: Rapid movements cause noticeable artifacts in video deepfakes as the tracking system struggles to maintain accurate landmark positioning. 
    • Occlusion handling: When objects pass over the AI-generated content such as the face, deepfake systems tend to fail at properly reconstructing the partially obscured face.
    • Lighting adaptation: Changes in lighting conditions might reveal inconsistencies in the rendering of the face
    • Audio-visual synchronization: Slight delays between lip movements and speech are detectable under careful observation
      • Exaggerated facial expressions. 
      • Duplicative or improperly placed appendages.
      • Pixelation or tearing at edges of face, eyes, ears, and glasses.
• Engage counterintelligence or insider risk/threat teams to:
  • Understand tradecraft and likely next steps
  • Gain national-level threat context, if applicable
• Make incremental, risk-based investigative and response decisions with the support of your insider threat working group and your insider threat stakeholder group; one providing tactical feedback and the other providing risk tolerance feedback.
• Preserve evidence and document findings.
• Share lessons learned and increase awareness.
• Educate employees on the risks associated with insider threats and provide regular security training for employees to recognize and respond to threats, including a section on the unique threat posed by North Korean IT workers.

After an insider risk response to Jasper Sleet, it might be necessary to also conduct a thorough forensic investigation of all systems that the employee had access to for indicators of persistence, such as RMM tools or system/resource modifications.

For additional resources, refer to CISA’s Insider Threat Mitigation Guide. If you suspect your organization is being targeted by nation-state cyber activity, report it to the appropriate national authority. For US-based organizations, the Federal Bureau of Investigation (FBI) recommends reporting North Korean remote IT worker activity to the Internet Crime Complaint Center (IC3).

Microsoft Defender XDR detections

Microsoft Defender XDR customers can refer to the list of applicable detections below. Microsoft Defender XDR coordinates detection, prevention, investigation, and response across endpoints, identities, email, apps to provide integrated protection against attacks like the threat discussed in this blog.

Customers with provisioned access can also use Microsoft Security Copilot in Microsoft Defender to investigate and respond to incidents, hunt for threats, and protect their organization with relevant threat intelligence.

Microsoft Defender XDR

Alerts with the following title in the security center can indicate threat activity on your network:

• Sign-in activity by a suspected North Korean entity

Microsoft Defender for Endpoint

Alerts with the following titles in the security center can indicate Jasper Sleet RMM activity on your network. These alerts, however, can be triggered by unrelated threat activity.

• Suspicious usage of remote management software
• Suspicious connection to remote access software

Microsoft Defender for Identity

Alerts with the following titles in the security center can indicate atypical identity access on your network. These alerts, however, can be triggered by unrelated threat activity.

• Atypical travel
• Suspicious behavior: Impossible travel activity

Microsoft Entra ID Protection

Microsoft Entra ID Protection risk detections inform Entra ID user risk events and can indicate associated threat activity, including unusual user activity consistent with known patterns identified by Microsoft Threat Intelligence research. Note, however, that these alerts can be also triggered by unrelated threat activity.

• Microsoft Entra threat intelligence (sign-in): (RiskEventType: investigationsThreatIntelligence)

Microsoft Defender for Cloud Apps

Alerts with the following titles in the security center can indicate atypical identity access on your network. These alerts, however, can be triggered by unrelated threat activity.

• Impossible travel activity

Microsoft Security Copilot

Security Copilot customers can use the standalone experience to create their own prompts or run the following prebuilt promptbooks to automate incident response or investigation tasks related to this threat:

• Incident investigation
• Microsoft User analysis
• Threat actor profile

Note that some promptbooks require access to plugins for Microsoft products such as Microsoft Defender XDR or Microsoft Sentinel.

Hunting queries

Microsoft Defender XDR

Because organizations might have legitimate and frequent uses for RMM software, we recommend using the Microsoft Defender XDR advanced hunting queries available on GitHub to locate RMM software that hasn’t been endorsed by your organization for further investigation. In some cases, these results might include benign activity from legitimate users. Regardless of use case, all newly installed RMM instances should be scrutinized and investigated.

If any queries have high fidelity for discovering unsanctioned RMM instances in your environment, and don’t detect benign activity, you can create a custom detection rule from the advanced hunting query in the Microsoft Defender portal. 

Microsoft Sentinel

The alert Insider Risk Sensitive Data Access Outside Organizational Geo-locationjoins Azure Information Protection logs (InformationProtectionLogs_CL) with Microsoft Entra ID sign-in logs (SigninLogs) to provide a correlation of sensitive data access by geo-location. Results include:

• User principal name
• Label name
• Activity
• City
• State
• Country/Region
• Time generated

The recommended configuration is to include (or exclude) sign-in geo-locations (city, state, country and/or region) for trusted organizational locations. There is an option for configuration of correlations against Microsoft Sentinel watchlists. Accessing sensitive data from a new or unauthorized geo-location warrants further review.

References

• https://www.justice.gov/opa/pr/two-north-korean-nationals-and-three-facilitators-indicted-multi-year-fraudulent-remote
• https://www.justice.gov/usao-dc/media/1352191/dl
• https://www.reuters.com/technology/north-koreans-use-fake-names-scripts-land-remote-it-work-cash-2023-11-21/
• https://github.com/jischell-msft/RemoteManagementMonitoringTools

Acknowledgments

For more information on North Korean remote IT worker operations, we recommend reviewing DTEX’s in-depth analysis in the report Exposing DPRK’s Cyber Syndicate and IT Workforce.

Learn more

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For the latest security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog. 

To get notified about new publications and to join discussions on social media, follow us on LinkedIn, X (formerly Twitter), and Bluesky. 

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The post Jasper Sleet: North Korean remote IT workers’ evolving tactics to infiltrate organizations appeared first on Microsoft Security Blog.

Agents with the Federal Bureau of Investigation (FBI) briefed Capitol Hill staff recently on hardening the security of their mobile devices, after a contacts list stolen from the personal phone of the White House Chief of Staff Susie Wiles was reportedly used to fuel a series of text messages and phone calls impersonating her to U.S. lawmakers. But in a letter this week to the FBI, one of the Senate’s most tech-savvy lawmakers says the feds aren’t doing enough to recommend more appropriate security protections that are already built into most consumer mobile devices.

A screenshot of the first page from Sen. Wyden’s letter to FBI Director Kash Patel.

On May 29, The Wall Street Journal reported that federal authorities were investigating a clandestine effort to impersonate Ms. Wiles via text messages and in phone calls that may have used AI to spoof her voice. According to The Journal, Wiles told associates her cellphone contacts were hacked, giving the impersonator access to the private phone numbers of some of the country’s most influential people.

The execution of this phishing and impersonation campaign — whatever its goals may have been — suggested the attackers were financially motivated, and not particularly sophisticated.

“It became clear to some of the lawmakers that the requests were suspicious when the impersonator began asking questions about Trump that Wiles should have known the answers to—and in one case, when the impersonator asked for a cash transfer, some of the people said,” the Journal wrote. “In many cases, the impersonator’s grammar was broken and the messages were more formal than the way Wiles typically communicates, people who have received the messages said. The calls and text messages also didn’t come from Wiles’s phone number.”

Sophisticated or not, the impersonation campaign was soon punctuated by the murder of Minnesota House of Representatives Speaker Emerita Melissa Hortman and her husband, and the shooting of Minnesota State Senator John Hoffman and his wife. So when FBI agents offered in mid-June to brief U.S. Senate staff on mobile threats, more than 140 staffers took them up on that invitation (a remarkably high number considering that no food was offered at the event).

But according to Sen. Ron Wyden (D-Ore.), the advice the FBI provided to Senate staffers was largely limited to remedial tips, such as not clicking on suspicious links or attachments, not using public wifi networks, turning off bluetooth, keeping phone software up to date, and rebooting regularly.

“This is insufficient to protect Senate employees and other high-value targets against foreign spies using advanced cyber tools,” Wyden wrote in a letter sent today to FBI Director Kash Patel. “Well-funded foreign intelligence agencies do not have to rely on phishing messages and malicious attachments to infect unsuspecting victims with spyware. Cyber mercenary companies sell their government customers advanced ‘zero-click’ capabilities to deliver spyware that do not require any action by the victim.”

Wyden stressed that to help counter sophisticated attacks, the FBI should be encouraging lawmakers and their staff to enable anti-spyware defenses that are built into Apple’s iOS and Google’s Android phone software.

These include Apple’s Lockdown Mode, which is designed for users who are worried they may be subject to targeted attacks. Lockdown Mode restricts non-essential iOS features to reduce the device’s overall attack surface. Google Android devices carry a similar feature called Advanced Protection Mode.

Wyden also urged the FBI to update its training to recommend a number of other steps that people can take to make their mobile devices less trackable, including the use of ad blockers to guard against malicious advertisements, disabling ad tracking IDs in mobile devices, and opting out of commercial data brokers (the suspect charged in the Minnesota shootings reportedly used multiple people-search services to find the home addresses of his targets).

The senator’s letter notes that while the FBI has recommended all of the above precautions in various advisories issued over the years, the advice the agency is giving now to the nation’s leaders needs to be more comprehensive, actionable and urgent.

“In spite of the seriousness of the threat, the FBI has yet to provide effective defensive guidance,” Wyden said.

Nicholas Weaver is a researcher with the International Computer Science Institute, a nonprofit in Berkeley, Calif. Weaver said Lockdown Mode or Advanced Protection will mitigate many vulnerabilities, and should be the default setting for all members of Congress and their staff.

“Lawmakers are at exceptional risk and need to be exceptionally protected,” Weaver said. “Their computers should be locked down and well administered, etc. And the same applies to staffers.”

Weaver noted that Apple’s Lockdown Mode has a track record of blocking zero-day attacks on iOS applications; in September 2023, Citizen Lab documented how Lockdown Mode foiled a zero-click flaw capable of installing spyware on iOS devices without any interaction from the victim.

Earlier this month, Citizen Lab researchers documented a zero-click attack used to infect the iOS devices of two journalists with Paragon’s Graphite spyware. The vulnerability could be exploited merely by sending the target a booby-trapped media file delivered via iMessage. Apple also recently updated its advisory for the zero-click flaw (CVE-2025-43200), noting that it was mitigated as of iOS 18.3.1, which was released in February 2025.

Apple has not commented on whether CVE-2025-43200 could be exploited on devices with Lockdown Mode turned on. But HelpNetSecurity observed that at the same time Apple addressed CVE-2025-43200 back in February, the company fixed another vulnerability flagged by Citizen Lab researcher Bill Marczak: CVE-2025-24200, which Apple said was used in an extremely sophisticated physical attack against specific targeted individuals that allowed attackers to disable USB Restricted Mode on a locked device.

In other words, the flaw could apparently be exploited only if the attacker had physical access to the targeted vulnerable device. And as the old infosec industry adage goes, if an adversary has physical access to your device, it’s most likely not your device anymore.

I can’t speak to Google’s Advanced Protection Mode personally, because I don’t use Google or Android devices. But I have had Apple’s Lockdown Mode enabled on all of my Apple devices since it was first made available in September 2022. I can only think of a single occasion when one of my apps failed to work properly with Lockdown Mode turned on, and in that case I was able to add a temporary exception for that app in Lockdown Mode’s settings.

My main gripe with Lockdown Mode was captured in a March 2025 column by TechCrunch’s Lorenzo Francheschi-Bicchierai, who wrote about its penchant for periodically sending mystifying notifications that someone has been blocked from contacting you, even though nothing then prevents you from contacting that person directly. This has happened to me at least twice, and in both cases the person in question was already an approved contact, and said they had not attempted to reach out.

Although it would be nice if Apple’s Lockdown Mode sent fewer, less alarming and more informative alerts, the occasional baffling warning message is hardly enough to make me turn it off.

In today’s evolving cyber threat landscape, threat actors are committed to advancing the sophistication of their attacks. The increasing adoption of essential security features like multifactor authentication (MFA), passwordless solutions, and robust email protections has changed many aspects of the phishing landscape, and threat actors are more motivated than ever to acquire credentials—particularly for enterprise cloud environments. Despite these evolutions, social engineering—the technique of convincing or deceiving users into downloading malware, directly divulging credentials, or more—remains a key aspect of phishing attacks.

Implementing phishing-resistant and passwordless solutions, such as passkeys, can help organizations improve their security stance against advanced phishing attacks. Microsoft is dedicated to enhancing protections against phishing attacks and making it more challenging for threat actors to exploit human vulnerabilities. In this blog, I’ll cover techniques that Microsoft has observed threat actors use for phishing and social engineering attacks that aim to compromise cloud identities. I’ll also share what organizations can do to defend themselves against this constant threat.

While the examples in this blog do not represent the full range of phishing and social engineering attacks being leveraged against enterprises today, they demonstrate several efficient techniques of threat actors tracked by Microsoft Threat Intelligence. Understanding these techniques and hardening your organization with the guidance included here will help contribute to a significant part of your defense-in-depth approach.

Pre-compromise techniques for stealing identities

Modern phishing techniques attempt to defeat authentication flows

Adversary-in-the-middle (AiTM)

Today’s authentication methods have changed the phishing landscape. The most prevalent example is the increase in adversary-in-the-middle (AiTM) credential phishing as the adoption of MFA grows. The phish kits available from phishing-as-a-service (PhaaS) platforms has further increased the impact of AiTM threats; the Evilginx phish kit, for example, has been used by multiple threat actors in the past year, from the prolific phishing operator Storm-0485 to the Russian espionage actor Star Blizzard.

Evilginx is an open-source framework that provides AiTM capabilities by deploying a proxy server between a target user and the website that the user wishes to visit (which the threat actor impersonates). Microsoft tracked Storm-0485 directing targets to Evilginx infrastructure using lures with themes such as payment remittance, shared documents, and fake LinkedIn account verifications, all designed to prompt a quick response from the recipient. Storm-0485 also consistently uses evasion tactics, notably passing initial links through obfuscated Google Accelerated Mobile Pages (AMP) URLs to make links harder to identify as malicious.

To protect against AiTM attacks, consider complementing MFA with risk-based Conditional Access policies, available in Microsoft Entra ID Protection, where sign-in requests are evaluated using additional identity-driven signals like IP address location information or device status, among others. These policies use real-time and offline detections to assess the risk level of sign-in attempts and user activities. This dynamic evaluation helps mitigate risks associated with token replay and session hijacking attempts common in AiTM phishing campaigns.

Additionally, consider implementing Zero Trust network security solutions, such as Global Secure Access which provides a unified pane of glass for secure access management of networks, identities, and endpoints.

Device code phishing

Device code phishing is a relatively new technique that has been incorporated by multiple threat actors into their attacks. In device code phishing, threat actors like Storm-2372 exploit the device code authentication flow to capture authentication tokens, which they then use to access target accounts. Storm-1249, a China-based espionage actor, typically uses generic phishing lures—with topics like taxes, civil service, and even book pre-orders—to target high-level officials at organizations of interest. Microsoft has also observed device code phishing being used for post-compromise activity, which are discussed more in the next sections.

At Microsoft, we strongly encourage organizations to block device code flow where possible; if needed, configure Microsoft Entra ID’s device code flow in your Conditional Access policies.

OAuth consent phishing

Another modern phishing technique is OAuth consent phishing, where threat actors employ the Open Authorization (OAuth) protocol and send emails with a malicious consent link for a third-party application. Once the target clicks the link and authorizes the application, the threat actor gains access tokens with the requested scopes and refresh tokens for persistent access to the compromised account. In one OAuth consent phishing campaign recently identified by Microsoft, even if a user declines the requested app permissions (by clicking Cancel on the prompt), the user is still sent to the app’s reply URL, and from there redirected to an AiTM domain for a second phishing attempt.

You can prevent employees from providing consent to specific apps or categories of apps that are not approved by your organization by configuring app consent policies to restrict user consent operations. For example, configure policies to allow user consent only to apps requesting low-risk permissions with verified publishers, or apps registered within your tenant.

Device join phishing

Finally, it’s worth highlighting recent device join phishing operations, where threat actors use a phishing link to trick targets into authorizing the domain-join of an actor-controlled device. Since April 2025, Microsoft has observed suspected Russian-linked threat actors using third-party application messages or emails referencing upcoming meeting invitations to deliver a malicious link containing valid authorization code. When clicked, the link returns a token for the Device Registration Service, allowing registration of the threat actor’s device to the tenant. You can harden against this type of phishing attack by requiring authentication strength for device registration in your environment.

Lures remain an effective phishing weapon

While both end users and automated security measures have become more capable at identifying malicious phishing attachments and links, motivated threat actors continue to rely on exploiting human behavior with convincing lures. As these attacks hinge on deceiving users, user training and awareness of commonly identified social engineering techniques are key to defending against them.

Impersonation lures

One of the most effective ways Microsoft has observed threat actors deliver lures is by impersonating people familiar to the target or using malicious infrastructure spoofing legitimate enterprise resources. In the last year, Star Blizzard has shifted from primarily using weaponized document attachments in emails to spear phishing with a malicious link leading to an AiTM page to target the government, non-governmental organizations (NGO), and academic sectors. The threat actor’s highly personalized emails impersonate individuals from whom the target would reasonably expect to receive emails, including known political and diplomatic figures, making the target more likely to be deceived by the phishing attempt.

QR codes

We have seen threat actors regularly iterating on the types of lure links incorporated into their attacks to make social engineering more effective. As QR codes have become a ubiquitous feature in communications, threat actors have adopted their use as well. For example, over the past two years, Microsoft has seen multiple actors incorporate QR codes, encoded with links to AiTM phishing pages, into opportunistic tax-themed phishing campaigns.

The threat actor Star Blizzard has even leveraged nonfunctional QR codes as a part of a spear-phishing campaign offering target users an opportunity to join a WhatsApp group: the initial spear-phishing email contained a broken QR code to encourage the targeted users to contact the threat actor. Star Blizzard’s follow-on email included a URL that redirected to a webpage with a legitimate QR code, used by WhatsApp for linking a device to a user’s account, giving the actor access to the user’s WhatsApp account.

Use of AI

Threat actors are increasingly leveraging AI to enhance the quality and volume of phishing lures. As AI tools become more accessible, these actors are using them to craft more convincing and sophisticated lures. In a collaboration with OpenAI, Microsoft Threat Intelligence has seen threat actors such as Emerald Sleet and Crimson Sandstorm interacting with large language models (LLMs) to support social engineering operations. This includes activities such as drafting phishing emails and generating content likely intended for spear-phishing campaigns.

We have also seen suspected use of generative AI to craft messages in a large-scale credential phishing campaign against the hospitality industry, based on the variations of language used across identified samples. The initial email contains a request for information designed to elicit a response from the target and is then followed by a more generic phishing email containing a lure link to an AiTM phishing site.

AI helps eliminate the common grammar mistakes and awkward phrasing that once made phishing attempts easier to spot. As a result, today’s phishing lures are more polished and harder for users to detect, increasing the likelihood of successful compromise. This evolution underscores the importance of securing identities in addition to user awareness training.

Phishing risks continue to expand beyond email

Enterprise communication methods have diversified to support distributed workforce and business operations, so phishing has expanded well beyond email messages. Microsoft has seen multiple threat actors abusing enterprise communication applications to deliver phishing messages, and we’ve also observed continued interest by threat actors to leverage non-enterprise applications and social media sites to reach targets.

Teams phishing

Microsoft Threat Intelligence has been closely tracking and responding to the abuse of the Microsoft Teams platform in phishing attacks and has taken action against confirmed malicious tenants by blocking their ability to send messages. The cybercrime access broker Storm-1674, for example, creates fraudulent tenants to create Teams meetings to send chat messages to potential victims using the meeting’s chat functionality; more recently, since November 2024, the threat actor has started compromising tenants and directly calling users over Teams to phish for credentials as well. Businesses can follow our security best practices for Microsoft Teams to further defend against attacks from external tenants.

Leveraging social media

Outside of business-managed applications, employees’ activity on social media sites and third-party communication platforms has widened the digital footprint for phishing attacks. For instance, while the Iranian threat actor Mint Sandstorm primarily uses spear-phishing emails, they have also sent phishing links to targets on social media sites, including Facebook and LinkedIn, to target high-profile individuals in government and politics. Mint Sandstorm, like many threat actors, also customizes and enhances their phishing messages by gathering publicly available information, such as personal email addresses and contacts, of their targets on social media platforms. Global Secure Access (GSA) is one solution that can reduce this type of phishing activity and manage access to social media sites on company-owned devices.

Post-compromise identity attacks

In addition to using phishing techniques for initial access, in some cases threat actors leverage the identity acquired from their first-stage phishing attack to launch subsequent phishing attacks. These follow-on phishing activities enable threat actors to move laterally within an organization, maintain persistence across multiple identities, and potentially acquire access to a more privileged account or to a third-party organization.

You can harden your environment against internal phishing activity by configuring the Microsoft Defender for Office 365 Safe Links policy to apply to internal recipients as well as by educating users to be wary of unsolicited documents and to report suspected phishing messages.

AiTM phishing crafted using legitimate company resources

Storm-0539, a threat actor that persistently targets the retail industry for gift card fraud, uses their initial access to a compromised identity to acquire legitimate emails—such as help desk tickets—that serve as templates for phishing emails. The crafted emails contain links directing users to AiTM phishing pages that mimic the federated identity service provider of the compromised organization. Because the emails resemble the organization’s legitimate messages, lead to convincing AiTM landing pages, and are sent from an internal account, they could be highly convincing. In this way, Storm-0539 moves laterally, seeking an identity with access to key cloud resources.

Intra-organization device code phishing

In addition to their use of device code phishing for initial access, Storm-2372 also leverages this technique in their lateral movement operations. The threat actor uses compromised accounts to send out internal emails with subjects such as “Document to review” and containing a device code authentication phishing payload. Because of the way device code authentication works, the payloads only work for 15 minutes, so Microsoft has seen multiple waves of post-compromise phishing attacks as the threat actor searches for additional credentials.

Defending against credential phishing and social engineering

Defending against phishing attacks begins at the primary gateways: email and other communication platforms. Review our recommended settings for Exchange Online Protection and Microsoft Defender for Office 365, or the equivalent for your email security solution, to ensure your organization has established essential defenses and knows how to monitor and respond to threat activity.

A holistic security posture for phishing must also account for the human aspect of social engineering. Investing in user awareness training and phishing simulations is critical for arming employees with the needed knowledge to defend against tried-and-true social engineering methods. Training can also help when threat actors inevitably refine and improve their techniques. Attack simulation training in Microsoft Defender for Office 365, which also includes simulating phishing messages in Microsoft Teams, is one approach to running realistic attack scenarios in your organization.

Hardening credentials and cloud identities is also necessary to defend against phishing attacks. By implementing the principles of least privilege and Zero Trust, you can significantly slow down determined threat actors who may have been able to gain initial access and buy time for defenders to respond. To get started, follow our steps to configure Microsoft Entra with increased security.

As part of hardening cloud identities, authentication using passwordless solutions like passkeys is essential, and implementing MFA remains a core pillar in identity security. Use the Microsoft Authenticator app for passkeys and MFA, and complement MFA with conditional access policies, where sign-in requests are evaluated using additional identity-driven signals. Conditional access policies can also be scoped to strengthen privileged accounts with phishing resistant MFA. Your passkey and MFA policy can be further secured by only allowing MFA and passkey registrations from trusted locations and devices.

Finally, a Security Service Edge solution like Global Secure Access (GSA) provides identity-focused secure network access. GSA can help to secure access to any app or resource using network, identity, and endpoint access controls.

Among Microsoft Incident Response cases over the past year where we identified the initial access vector, almost a quarter incorporated phishing or social engineering. To achieve phishing resistance and limit the opportunity to exploit human behavior, begin planning for passkey rollouts in your organization today, and  at a minimum, prioritize phishing-resistant MFA for privileged accounts as you evaluate the effect of this security measure on your wider organization. In the meantime, use the other defense-in-depth approaches I’ve recommended in this blog to defend against phishing and social engineering attacks.

Stay vigilant and prioritize your security at every step.

Recommendations

Several recommendations were made throughout this blog to address some of the specific techniques being used by threat actors tracked by Microsoft, along with essential practices for securing identities. Here is a consolidated list for your security team to evaluate.

• Configure Microsoft Entra with increased security.
• Use the Microsoft Authenticator app for passkeys and MFA.
• Strengthen privileged accounts with phishing resistant MFA.
• Complement MFA with risk-based Conditional Access policies, where sign-in requests are evaluated using additional identity-driven signals like IP address location information or device status, among others. Implementing Microsoft Entra ID Protection with these policies can automatically block or challenge access based on indicators like unfamiliar sign-in patterns or potential token theft attempts. When combined with Global Secure Access (GSA), organizations can extend this protection by enforcing Conditional Access decisions at the network layer to help secure access to any app or resource.
• Only allowing MFA and passkey registrations from trusted locations and devices.
• Review our recommended settings for Exchange Online Protection and Microsoft Defender for Office 365.
• Use attack simulation training in Microsoft Defender for Office 365, which also includes simulating phishing messages in Microsoft Teams, to run realistic attack scenarios in your organization for educating users.
• Use Global Secure Access to secure access to any app or resource using network, identity, and endpoint access controls.
• Block device code flow where possible; if needed, configure Microsoft Entra ID’s device code flow in your Conditional Access policies.
• Configure app consent policies to restrict user consent operations. For example, configure policies to allow user consent only to apps requesting low-risk permissions with verified publishers, or apps registered within your tenant.
• Require authentication strength for device registration in your environment.
• Follow our security best practices for Microsoft Teams.
• Configure the Microsoft Defender for Office 365 Safe Links policy to apply to internal recipients.

At Microsoft, we are accelerating security with our work on the Secure by Default framework. Specific Microsoft-managed policies are enabled for every new tenant and raise your security posture with security defaults that provide a baseline of protection for Entra ID and resources like Office 365.

Learn more  

For the latest security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog. 

To get notified about new publications and to join discussions on social media, follow us on LinkedIn, X (formerly Twitter), and Bluesky. 

To hear stories and insights from the Microsoft Threat Intelligence community about the ever-evolving threat landscape, listen to the Microsoft Threat Intelligence podcast. 

The post Defending against evolving identity attack techniques appeared first on Microsoft Security Blog.

Over the past year, Microsoft observed the persistent growth and operational sophistication of Lumma Stealer, an infostealer malware used by multiple financially motivated threat actors to target various industries. Our investigation into Lumma Stealer’s distribution infrastructure reveals a dynamic and resilient ecosystem that spans phishing, malvertising, abuse of trusted platforms, and traffic distribution systems. These findings underscore the importance of collaborative efforts to disrupt cybercrime. Microsoft, partnering with others across industry and international law enforcement, recently facilitated a disruption of Lumma infrastructure.

Lumma Stealer (also known as LummaC2) is a malware as a service (MaaS) offering that is capable of stealing data from various browsers and applications such as cryptocurrency wallets and installing other malware. Microsoft Threat Intelligence tracks the threat actor who developed and maintains the Lumma malware, command-and-control (C2) infrastructure, and the Lumma MaaS as Storm-2477. Affiliates who pay Storm-2477 for the service and operate their own Lumma campaigns access a panel to build the malware binary and manage the C2 communications and stolen information. We have observed ransomware threat actors like Octo Tempest, Storm-1607, Storm-1113, and Storm-1674 using Lumma Stealer in campaigns.

Unlike earlier infostealers that relied heavily on bulk spam or exploits, Lumma Stealer exemplifies a shift toward multi-vector delivery strategies. Its operators demonstrate resourcefulness and proficiency in impersonation tactics. The Lumma Stealer distribution infrastructure is flexible and adaptable. Operators continually refine their techniques, rotating malicious domains, exploiting ad networks, and leveraging legitimate cloud services to evade detection and maintain operational continuity. This dynamic structure enables operators to maximize the success of campaigns while complicating efforts to trace or dismantle their activities.

The growth and resilience of Lumma Stealer highlights the broader evolution of cybercrime and underscores the need for layered defenses and industry collaboration to counter threats. In this blog post, we share our analysis of Lumma Stealer and its infrastructure and provide guidance on how users and organizations can protect themselves from this threat. Microsoft remains committed to sharing insights, developing protections, and working with partners across industries to disrupt malicious ecosystems and safeguard users worldwide.

Lumma Stealer delivery techniques

Lumma Stealer leverages a broad and evolving set of delivery vectors. Campaigns often combine multiple techniques, dynamically adapting to evade detection and increase infection success rates. Delivery infrastructure is designed to be ephemeral, shifting rapidly across domains, platforms, and geographies to avoid takedowns.

• Phishing emails: Lumma Stealer emails impersonate known brands and services to deliver links or attachments. These campaigns involve expertly crafted emails designed to evoke urgency, often masquerading as urgent hotel reservation confirmations or pending cancellations. The emails lead victims to cloned websites or malicious servers that deploy the Lumma payload to the targets’ environment.

• Malvertising: Threat actors inject fake advertisements into search engine results, targeting software-related queries such as “Notepad++ download” or “Chrome update.” Clicking these poisoned links leads users to cloned websites that closely mimic legitimate vendors but instead deliver the Lumma Stealer.
• Drive-by download on compromised websites: Threat actors were observed compromising groups of legitimate websites, typically through a particular vulnerability or misconfiguration. They modify site content by inserting malicious JavaScript. The JavaScript runs when sites are visited by unsuspecting users, leading to delivery of a payload, intermediary script, or displaying further lures to convince users to perform an action.
• Trojanized applications: In many campaigns, cracked or pirated versions of legitimate applications are bundled with Lumma binaries and distributed through file-sharing platforms. These modified installers often contain no visible payload during installation, executing the malware silently post-launch.
• Abuse of legitimate services and ClickFix: Public repositories like GitHub are abused and populated with scripts and binaries, often disguised as tools or utilities. A particularly deceptive method involves fake CAPTCHA pages, commonly observed in the ClickFix ecosystem. Targets are instructed to copy malicious commands into their system’s Run utility under the pretense of passing a verification check. These commands often download and execute Lumma directly in memory, using Base64 encoding and stealthy delivery chains.
• Dropped by other malware: Microsoft Threat Intelligence observed other loaders and malware such as DanaBot delivering Lumma Stealer as an additional payload.

All these mechanisms reflect threat actor behavior that prioritizes abuse of user trust, manipulation of legitimate infrastructure, and multi-layered distribution chains designed to evade both technical and human defenses. The following sections discuss some examples of campaigns where the mentioned distribution methods were used to deliver Lumma Stealer.

Drive-by download campaign leveraging EtherHiding and ClickFix to deliver Lumma

In early April 2025, Microsoft observed a cluster of compromised websites leveraging EtherHiding and ClickFix techniques to install Lumma Stealer. EtherHiding is a technique that involves leveraging smart contracts on blockchain platforms like Binance Smart Chain (BSC) to host parts of malicious code. Traditional methods of blocking malicious code, such as IP or domain blocking or content-based detections, are less effective against EtherHiding because the code is embedded in the blockchain. Meanwhile, in the ClickFix technique, a threat actor attempts to take advantage of human problem-solving tendencies by displaying fake error messages or prompts that instruct target users to fix issues by copying, pasting, and launching commands that eventually result in the download of malware.

In this campaign, the JavaScript injected into compromised websites directly contacted BSC to retrieve the ClickFix code and lure, which was then presented to the target. Users needed to click the “I’m not a robot” prompt, at which point a command was copied into their clipboard. Users were then instructed to paste and launch this command via the Windows Run prompt. The command downloaded and initiated further code using mshta from check.foquh[.]icu.

Email campaign targeting organizations in Canada to deliver Lumma Stealer

On April 7, 2025, Microsoft Threat Intelligence observed an email campaign consisting of thousands of emails targeting organizations in Canada. The emails used invoice lures for a fitness plan or an online education platform. The emails’ subject lines were personalized to include recipient-specific details such as “Invoice for [recipient email]”. Notably, the attack chain utilized multiple tools available for purchase on underground forums for traffic filtering and social engineering.

The emails contained URLs leading to the Prometheus traffic direction system (TDS) hosted on numerous compromised sites. The TDS in turn, redirected users to the attacker-controlled website binadata[.]com that hosted the ClickFix social engineering framework. Like the previous campaign, targets were instructed to click a “I’m not a robot” prompt and run malicious code via a multi-step process. The malicious code was an mshta command that downloaded and executed JavaScript from the IP address 185.147.125[.]174. The JavaScript ran a PowerShell command that downloaded more PowerShell code, which finally downloaded and launched a Lumma Stealer executable. Notably, Xworm malware was also bundled into this executable.

Lumma Stealer malware analysis

The core Lumma Stealer malware is written in a combination of C++ and ASM. The malware author designed it as a MaaS offering. Threat actors can access the panel to build the malware binary and manage the C2 communications and stolen information. The core binary is obfuscated with advanced protection such as low-level virtual machine (LLVM core), Control Flow Flattening (CFF), Control Flow Obfuscation, customized stack decryption, huge stack variables, and dead codes, among others. These techniques are implemented on the critical functions to make static analysis difficult, as these can cause tools like Hex-Rays’ IDA fail to produce equivalent decompiled codes. In addition, most of the critical APIs are implemented via low-level syscalls and Heavens Gate Technology.

Lumma Stealer is designed to steal from browsers based on Chromium and Mozilla technology, including Microsoft Edge. In addition, it has the capability to install other malware or plugins, including Clipboard stealer plugin and coin miners, either by downloading to disk or directly in memory.

Process injection and process hollowing

Lumma loader may use process hollowing to inject its malicious payload into legitimate system processes like msbuild.exe, regasm.exe, regsvcs.exe, and explorer.exe. This technique enables execution under the guise of a trusted binary to bypass behavioral detection and endpoint monitoring tools.

Information-stealing capabilities

Lumma Stealer targets a comprehensive set of user data using a specialized collection routine for each type of data. These capabilities have evolved over time, and Microsoft Threat Intelligence has recently observed that the instructions for the target credentials are specified in the configuration file retrieved from the active C2 server. The configuration file is divided into several parts: the “ex” section that pertains to the target list of apps for cryptocurrency wallets and extensions, and “c” sections that pertain to the list of applications and configuration details for browsers, user file’s locations, and other applications.

• Browser credentials and cookies: Lumma Stealer extracts saved passwords, session cookies, and autofill data from Chromium (including Edge), Mozilla, and Gecko-based browsers.
• Cryptocurrency wallets and extensions: Lumma Stealer actively searches for wallet files, browser extensions, and local keys associated with wallets like MetaMask, Electrum, and Exodus.
• Various applications: Lumma Stealer targets data from various virtual private networks (VPNs) (.ovpn), email clients, FTP clients, and Telegram applications.  
• User documents: Lumma Stealer harvests files found on the user profiles and other common directories, especially those with .pdf, .docx, or .rtf extensions.
• System metadata: Lumma Stealer collects host telemetry such as CPU information, OS version, system locale, and installed applications for tailoring future exploits or profiling victims.

C2 communication

Lumma Stealer maintains a robust C2 infrastructure, using a combination of hardcoded tier 1 C2s that are regularly updated and reordered, and fallback C2s hosted as Steam profiles and Telegram channels that also point to the tier 1 C2s. The Telegram C2, if available, is always checked first, while the Steam C2 is checked only when all the hardcoded C2s are not active. To further hide the real C2 servers, all the C2 servers are hidden behind the Cloudflare proxy.

While Lumma Stealer affiliates share the tier 1 C2s, there is a capability to add a personal tier 1 C2 domain for an extra cost. The diagram below shows an overview of the Lumma Stealer infrastructure. All traffic is encrypted by HTTPS.

Different types of obfuscation are applied to each set of C2 servers. For example, the hardcoded list of C2s, and including the Telegram fallback C2 URL are protected with ChaCha20 crypto, while the Steam profile fallback C2 URL is encrypted using custom stack-based crypto algorithm that can change on each version of Lumma malware.

We have identified up to six versions of Lumma Stealer, and while each of these versions focuses on improving techniques to evade antivirus detections, there are also several changes in the C2 communication protocol and formats such as the C2 domains, URI path, POST data, and others. The core Lumma malware stores the build date as part of the embedded configuration to keep track of improvements, but in our investigation, we tracked major changes using the labels “version 1” through “version 6”.

Lumma Stealer keeps track of the active C2 for sending the succeeding commands. Each command is sent to a single C2 domain that is active at that point. In addition, each C2 command contains one or more C2 parameters specified as part of the POST data as form data. The parameters are:  

• act: Indicates the C2 command. Note: This C2 parameter no longer exists in Lumma version 6.
• ver: Indicates C2 protocol version. This value is always set to 4.0 and has never changed since the first version Lumma.
• lid (for version 5 and below)/uid (for version 6): This ID identifies the Lumma client/operator and its campaign.
• j (for version 5 and below )/cid (for version 6): This is an optional field that identifies additional Lumma features.
• hwid: Indicates the unique identifier for the victim machine.
• pid: Used in SEND_MESSAGE command to identify the source of the stolen data. A value of 1, indicates it came from the Lumma core process.

The following are some of the most common Lumma Stealer C2 commands and associated parameters:

• PING / LIFE: Initial command to check if the C2 is active. Note: This command does not exist in version 6.
  • act=life
• RECEIVE_MESSAGE: Command to download the stealer’s configuration. As noted above, this contains the specifications on the list of targets.
  • version 3 and below: act=recive_message&ver=4.0&lid=[<lid_value>]&j=[<j_value>]
  • version 4 and 5: act=receive_message&ver=4.0&lid=[<lid_value>]&j=[<j_value>]
  • version 6: uid=<uid_value>&cid=[<cid_value>]
• SEND_MESSAGE: Command to send back stolen data in chunks. The C2 parameters are specified as individual section in the whole POST data. The fields included are act=send_message, hwid, pid, lid/uid, and j/cid. The act field was removed in version 6.
• GET_MESSAGE: Command to download the second configuration. This configuration contains information about the plugins and additional malware to install on the target systems. We have observed that in most cases this command will respond with valid but empty records “[]”, meaning nothing to download. So far, we have observed Lumma Stealer installing an updated version of the Clipboard stealer plugin and coin miners.
  • versions 5 and below: act=get_message&ver=4.0&lid=[<lid_value>]&j=[<j_value>]&hwid=<hwid_value>
  • version 6: uid=<uid_value>&cid=[<cid_value>]&hwid=<hwid_value>

Microsoft Digital Crimes Unit (DCU) engineered tools that identify and map the Lumma Stealer C2 infrastructure. As part of the disruption announced on May 21, Microsoft’s DCU has facilitated the takedown, suspension, and blocking of approximately 2,300 malicious domains that formed the backbone of the Lumma Stealer infrastructure.  More details of this operation are presented in the DCU disruption announcement.

Recommendations

Microsoft Threat Intelligence recommends the following mitigations to reduce the impact of this threat.

Strengthen Microsoft Defender for Endpoint configuration

• Ensure that tamper protection is enabled in Microsoft Defender for Endpoint.
• Enable network protection in Microsoft Defender for Endpoint.
• Turn on web protection.
• Run endpoint detection and response (EDR) in block mode so that Microsoft Defender for Endpoint can block malicious artifacts, even when your non-Microsoft antivirus does not detect the threat or when Microsoft Defender Antivirus is running in passive mode. EDR in block mode works behind the scenes to remediate malicious artifacts that are detected post-breach.    
• Configure investigation and remediation in full automated mode to let Microsoft Defender for Endpoint take immediate action on alerts to resolve breaches, significantly reducing alert volume. 
• Microsoft Defender XDR customers can turn on the following attack surface reduction rules to prevent common attack techniques used by threat actors.
  • Block executable files from running unless they meet a prevalence, age, or trusted list criterion
  • Block execution of potentially obfuscated scripts
  • Block JavaScript or VBScript from launching downloaded executable content
  • Block process creations originating from PSExec and WMI commands
  • Block credential stealing from the Windows local security authority subsystem
  • Block use of copied or impersonated system tools

Strengthen operating environment configuration

• Require multifactor authentication (MFA). While certain attacks such as adversary-in-the-middle (AiTM) phishing attempt to circumvent MFA, implementation of MFA remains an essential pillar in identity security and is highly effective at stopping a variety of threats.
• Leverage phishing-resistant authentication methods such as FIDO Tokens, or Microsoft Authenticator with passkey. Avoid telephony-based MFA methods to avoid risks associated with SIM-jacking.
• Implement Entra ID Conditional Access authentication strength to require phishing-resistant authentication for employees and external users for critical apps.
• Encourage users to use Microsoft Edge with Microsoft Defender SmartScreen, which identifies and blocks malicious websites, including phishing sites, scam sites, and sites that host malware.
• Enable Network Level Authentication for Remote Desktop Service connections.
• Enable Local Security Authority (LSA) protection to block credential stealing from the Windows local security authority subsystem.
• AppLocker can restrict specific software tools prohibited within the organization, such as reconnaissance, fingerprinting, and RMM tools, or grant access to only specific users.

Detection details

Microsoft Defender XDR customers can refer to the list of applicable detections below. Microsoft Defender XDR coordinates detection, prevention, investigation, and response across endpoints, identities, email, apps to provide integrated protection against attacks like the threat discussed in this blog.

Customers with provisioned access can also use Microsoft Security Copilot in Microsoft Defender to investigate and respond to incidents, hunt for threats, and protect their organization with relevant threat intelligence.

Microsoft Defender Antivirus

Microsoft Defender Antivirus detects this threat as the following malware:

• Behavior:Win32/LummaStealer
• Trojan:JS/LummaStealer
• Trojan:MSIL/LummaStealer
• Trojan:Win32/LummaStealer
• Trojan:Win64/LummaStealer
• TrojanDropper:Win32/LummaStealer
• Trojan:PowerShell/Powdow
• Trojan:Win64/Shaolaod
• Behavior:Win64/Shaolaod
• Behavior:Win32/MaleficAms
• Behavior:Win32/ClickFix
• Behavior:Win32/SuspClickFix
• Trojan:Win32/ClickFix
• Trojan:PowerShell/ClickFixObfus
• Behavior:Win32/RegRunMRU
• Trojan:HTML/FakeCaptcha
• Trojan:Script/SuspDown

Microsoft Defender for Endpoint

The following Microsoft Defender for Endpoint alerts might also indicate threat activity related to this threat. Note, however, that these alerts can be also triggered by unrelated threat activity:

• Suspicious command in RunMRU registry
• Possible Lumma Stealer activity
• Information stealing malware activity
• Suspicious PowerShell command line
• Use of living-off-the-land binary to run malicious code
• Possible theft of passwords and other sensitive web browser information
• Suspicious DPAPI Activity
• Suspicious mshta process launched
• Renamed AutoIt tool
• Suspicious phishing activity detected
• Suspicious implant process from a known emerging threat
• A process was injected with potentially malicious code
• Process hollowing detected
• Suspicious PowerShell download or encoded command execution
• A process was launched on a hidden desktop

Microsoft Defender for Office 365

Microsoft Defender for Office 365 identifies and blocks malicious emails. These alerts, however, can also be triggered by unrelated threat activity:

• A potentially malicious URL click was detected
• Email messages containing malicious URL removed after delivery
• Email messages removed after delivery
• A user clicked through to a potentially malicious URL
• Suspicious email sending patterns detected
• Email reported by user as malware or phish

Defender for Office 365 also detects and blocks Prometheus TDS, EtherHiding patterns, ClickFix landing pages.

Microsoft Security Copilot

Security Copilot customers can use the standalone experience to create their own prompts or run the following pre-built promptbooks to automate incident response or investigation tasks related to this threat:

• Incident investigation
• Microsoft User analysis
• Threat actor profile
• Threat Intelligence 360 report based on MDTI article
• Vulnerability impact assessment

Note that some promptbooks require access to plugins for Microsoft products such as Microsoft Defender XDR or Microsoft Sentinel.

Threat intelligence reports

Microsoft customers can use the following reports in Microsoft products to get the most up-to-date information about the threat actor, malicious activity, and techniques discussed in this blog. These reports provide the intelligence, protection information, and recommended actions to prevent, mitigate, or respond to associated threats found in customer environments.

Microsoft Defender Threat Intelligence

• Storm-1865 phishing campaigns over vendor platforms lead to payment data theft and fraudulent charges
• Lumma Stealer
• Malvertising campaign leads to info stealers hosted on GitHub
• ClickFix technique leverages clipboard to run malicious commands

Microsoft Security Copilot customers can also use the Microsoft Security Copilot integration in Microsoft Defender Threat Intelligence, either in the Security Copilot standalone portal or in the embedded experience in the Microsoft Defender portal to get more information about this threat actor.

Hunting queries

Microsoft Defender XDR

Microsoft Defender XDR customers can run the following query to find related activity in their networks:

ClickFix commands execution

Identify ClickFix commands execution.

DeviceRegistryEvents
| where ActionType =~ "RegistryValueSet"
| where InitiatingProcessFileName =~ "explorer.exe"
| where RegistryKey has @"\CurrentVersion\Explorer\RunMRU"
| where RegistryValueData has "✅"
        or (RegistryValueData has_any ("powershell", "mshta", "curl", "msiexec", "^")
             and RegistryValueData matches regex "[\u0400-\u04FF\u0370-\u03FF\u0590-\u05FF\u0600-\u06FF\u0E00-\u0E7F\u2C80-\u2CFF\u13A0-\u13FF\u0530-\u058F\u10A0-\u10FF\u0900-\u097F]")
        or (RegistryValueData has "mshta" and RegistryValueName !~ "MRUList" and RegistryValueData !in~ ("mshta.exe\\1", "mshta\\1"))
        or (RegistryValueData has_any ("bitsadmin", "forfiles", "ProxyCommand=") and RegistryValueName !~ "MRUList")
        or ((RegistryValueData startswith "cmd" or RegistryValueData startswith "powershell")
            and (RegistryValueData has_any ("-W Hidden ", " -eC ", "curl", "E:jscript", "ssh", "Invoke-Expression", "UtcNow", "Floor", "DownloadString", "DownloadFile", "FromBase64String",  "System.IO.Compression", "System.IO.MemoryStream", "iex", "Invoke-WebRequest", "iwr", "Get-ADDomainController", "InstallProduct", "-w h", "-X POST", "Invoke-RestMethod", "-NoP -W", ".InVOKe", "-useb", "irm ", "^", "[char]", "[scriptblock]", "-UserAgent", "UseBasicParsing", ".Content")
              or RegistryValueData matches regex @"[-/–][Ee^]{1,2}[NnCcOoDdEeMmAa^]*\s[A-Za-z0-9+/=]{15,}"))

DPAPI decryption via AutoIT or .NET Framework processes

Identify DPAPI decryption activity originating from AutoIT scripts .NET Framework processes.

DeviceEvents
| where ActionType == "DpapiAccessed"
| where InitiatingProcessVersionInfoInternalFileName == "AutoIt3.exe"
      or InitiatingProcessFolderPath has "\\windows\\microsoft.net\\framework\\"
      or InitiatingProcessFileName =~ "powershell.exe"
| where (AdditionalFields has_any("Google Chrome", "Microsoft Edge") and AdditionalFields has_any("SPCryptUnprotect"))
| extend json = parse_json(AdditionalFields)
| extend dataDesp = tostring(json.DataDescription.PropertyValue)
| extend opType = tostring(json.OperationType.PropertyValue)
| where dataDesp in~ ("Google Chrome", "Microsoft Edge", "Chromium", "Opera", "Opera GX", "IMAP Password", "Brave Browser", "AVG Secure Browser") 
        and opType =~ "SPCryptUnprotect"
| project Timestamp, ReportId, DeviceId, ActionType, InitiatingProcessParentFileName, InitiatingProcessFileName, InitiatingProcessVersionInfoInternalFileName, InitiatingProcessCommandLine, AdditionalFields, dataDesp, opType

Sensitive browser file access via AutoIT or .NET Framework processes

Identify .NET Framework processes (such as RegAsm.exe, MSBuild.exe, etc.) accessing sensitive browser files.

let browserDirs = pack_array(@"\Google\Chrome\User Data\", @"\Microsoft\Edge\User Data\", @"\Mozilla\Firefox\Profiles\"); 
let browserSensitiveFiles = pack_array("Web Data", "Login Data", "key4.db", "formhistory.sqlite", "cookies.sqlite", "logins.json", "places.sqlite", "cert9.db");
DeviceEvents
| where AdditionalFields has_any ("FileOpenSource") // Filter for "File Open" events.
| where InitiatingProcessVersionInfoInternalFileName == "AutoIt3.exe"
      or InitiatingProcessImageFilePath has "\\windows\\microsoft.net\\framework\\"
      or InitiatingProcessFileName =~ "powershell.exe"
| where (AdditionalFields has_any(browserDirs) or  AdditionalFields has_any(browserSensitiveFiles)) 
| extend json = parse_json(AdditionalFields)
| extend File_Name = tostring(json.FileName.PropertyValue)
| where (File_Name has_any (browserDirs) and File_Name has_any (browserSensitiveFiles))
| project Timestamp, ReportId, DeviceId, InitiatingProcessParentFileName, InitiatingProcessFileName, InitiatingProcessVersionInfoInternalFileName, InitiatingProcessCommandLine, File_Name

Learn more

For the latest security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog: https://aka.ms/threatintelblog.

To get notified about new publications and to join discussions on social media, follow us on LinkedIn at https://www.linkedin.com/showcase/microsoft-threat-intelligence, on X (formerly Twitter) at https://x.com/MsftSecIntel, and Bluesky at https://bsky.app/profile/threatintel.microsoft.com.

To hear stories and insights from the Microsoft Threat Intelligence community about the ever-evolving threat landscape, listen to the Microsoft Threat Intelligence podcast: https://thecyberwire.com/podcasts/microsoft-threat-intelligence.

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KrebsOnSecurity last week was hit by a near record distributed denial-of-service (DDoS) attack that clocked in at more than 6.3 terabits of data per second (a terabit is one trillion bits of data). The brief attack appears to have been a test run for a massive new Internet of Things (IoT) botnet capable of launching crippling digital assaults that few web destinations can withstand. Read on for more about the botnet, the attack, and the apparent creator of this global menace.

For reference, the 6.3 Tbps attack last week was ten times the size of the assault launched against this site in 2016 by the Mirai IoT botnet, which held KrebsOnSecurity offline for nearly four days. The 2016 assault was so large that Akamai – which was providing pro-bono DDoS protection for KrebsOnSecurity at the time — asked me to leave their service because the attack was causing problems for their paying customers.

Since the Mirai attack, KrebsOnSecurity.com has been behind the protection of Project Shield, a free DDoS defense service that Google provides to websites offering news, human rights, and election-related content. Google Security Engineer Damian Menscher told KrebsOnSecurity the May 12 attack was the largest Google has ever handled. In terms of sheer size, it is second only to a very similar attack that Cloudflare mitigated and wrote about in April.

After comparing notes with Cloudflare, Menscher said the botnet that launched both attacks bears the fingerprints of Aisuru, a digital siege machine that first surfaced less than a year ago. Menscher said the attack on KrebsOnSecurity lasted less than a minute, hurling large UDP data packets at random ports at a rate of approximately 585 million data packets per second.

“It was the type of attack normally designed to overwhelm network links,” Menscher said, referring to the throughput connections between and among various Internet service providers (ISPs). “For most companies, this size of attack would kill them.”

A graph depicting the 6.5 Tbps attack mitigated by Cloudflare in April 2025. Image: Cloudflare.

The Aisuru botnet comprises a globally-dispersed collection of hacked IoT devices, including routers, digital video recorders and other systems that are commandeered via default passwords or software vulnerabilities. As documented by researchers at QiAnXin XLab, the botnet was first identified in an August 2024 attack on a large gaming platform.

Aisuru reportedly went quiet after that exposure, only to reappear in November with even more firepower and software exploits. In a January 2025 report, XLab found the new and improved Aisuru (a.k.a. “Airashi“) had incorporated a previously unknown zero-day vulnerability in Cambium Networks cnPilot routers.

NOT FORKING AROUND

The people behind the Aisuru botnet have been peddling access to their DDoS machine in public Telegram chat channels that are closely monitored by multiple security firms. In August 2024, the botnet was rented out in subscription tiers ranging from $150 per day to $600 per week, offering attacks of up to two terabits per second.

“You may not attack any measurement walls, healthcare facilities, schools or government sites,” read a notice posted on Telegram by the Aisuru botnet owners in August 2024.

Interested parties were told to contact the Telegram handle “@yfork” to purchase a subscription. The account @yfork previously used the nickname “Forky,” an identity that has been posting to public DDoS-focused Telegram channels since 2021.

According to the FBI, Forky’s DDoS-for-hire domains have been seized in multiple law enforcement operations over the years. Last year, Forky said on Telegram he was selling the domain stresser[.]best, which saw its servers seized by the FBI in 2022 as part of an ongoing international law enforcement effort aimed at diminishing the supply of and demand for DDoS-for-hire services.

“The operator of this service, who calls himself ‘Forky,’ operates a Telegram channel to advertise features and communicate with current and prospective DDoS customers,” reads an FBI seizure warrant (PDF) issued for stresser[.]best. The FBI warrant stated that on the same day the seizures were announced, Forky posted a link to a story on this blog that detailed the domain seizure operation, adding the comment, “We are buying our new domains right now.”

A screenshot from the FBI’s seizure warrant for Forky’s DDoS-for-hire domains shows Forky announcing the resurrection of their service at new domains.

Approximately ten hours later, Forky posted again, including a screenshot of the stresser[.]best user dashboard, instructing customers to use their saved passwords for the old website on the new one.

A review of Forky’s posts to public Telegram channels — as indexed by the cyber intelligence firms Unit 221B and Flashpoint — reveals a 21-year-old individual who claims to reside in Brazil [full disclosure: Flashpoint is currently an advertiser on this blog].

Since late 2022, Forky’s posts have frequently promoted a DDoS mitigation company and ISP that he operates called botshield[.]io. The Botshield website is connected to a business entity registered in the United Kingdom called Botshield LTD, which lists a 21-year-old woman from Sao Paulo, Brazil as the director. Internet routing records indicate Botshield (AS213613) currently controls several hundred Internet addresses that were allocated to the company earlier this year.

Domaintools.com reports that botshield[.]io was registered in July 2022 to a Kaike Southier Leite in Sao Paulo. A LinkedIn profile by the same name says this individual is a network specialist from Brazil who works in “the planning and implementation of robust network infrastructures, with a focus on security, DDoS mitigation, colocation and cloud server services.”

MEET FORKY

Image: Jaclyn Vernace / Shutterstock.com.

In his posts to public Telegram chat channels, Forky has hardly attempted to conceal his whereabouts or identity. In countless chat conversations indexed by Unit 221B, Forky could be seen talking about everyday life in Brazil, often remarking on the extremely low or high prices in Brazil for a range of goods, from computer and networking gear to narcotics and food.

Reached via Telegram, Forky claimed he was “not involved in this type of illegal actions for years now,” and that the project had been taken over by other unspecified developers. Forky initially told KrebsOnSecurity he had been out of the botnet scene for years, only to concede this wasn’t true when presented with public posts on Telegram from late last year that clearly showed otherwise.

Forky denied being involved in the attack on KrebsOnSecurity, but acknowledged that he helped to develop and market the Aisuru botnet. Forky claims he is now merely a staff member for the Aisuru botnet team, and that he stopped running the botnet roughly two months ago after starting a family. Forky also said the woman named as director of Botshield is related to him.

Forky offered equivocal, evasive responses to a number of questions about the Aisuru botnet and his business endeavors. But on one point he was crystal clear:

“I have zero fear about you, the FBI, or Interpol,” Forky said, asserting that he is now almost entirely focused on their hosting business — Botshield.

Forky declined to discuss the makeup of his ISP’s clientele, or to clarify whether Botshield was more of a hosting provider or a DDoS mitigation firm. However, Forky has posted on Telegram about Botshield successfully mitigating large DDoS attacks launched against other DDoS-for-hire services.

DomainTools finds the same Sao Paulo street address in the registration records for botshield[.]io was used to register several other domains, including cant-mitigate[.]us. The email address in the WHOIS records for that domain is forkcontato@gmail.com, which DomainTools says was used to register the domain for the now-defunct DDoS-for-hire service stresser[.]us, one of the domains seized in the FBI’s 2023 crackdown.

On May 8, 2023, the U.S. Department of Justice announced the seizure of stresser[.]us, along with a dozen other domains offering DDoS services. The DOJ said ten of the 13 domains were reincarnations of services that were seized during a prior sweep in December, which targeted 48 top stresser services (also known as “booters”).

Forky claimed he could find out who attacked my site with Aisuru. But when pressed a day later on the question, Forky said he’d come up empty-handed.

“I tried to ask around, all the big guys are not retarded enough to attack you,” Forky explained in an interview on Telegram. “I didn’t have anything to do with it. But you are welcome to write the story and try to put the blame on me.”

THE GHOST OF MIRAI

The 6.3 Tbps attack last week caused no visible disruption to this site, in part because it was so brief — lasting approximately 45 seconds. DDoS attacks of such magnitude and brevity typically are produced when botnet operators wish to test or demonstrate their firepower for the benefit of potential buyers. Indeed, Google’s Menscher said it is likely that both the May 12 attack and the slightly larger 6.5 Tbps attack against Cloudflare last month were simply tests of the same botnet’s capabilities.

In many ways, the threat posed by the Aisuru/Airashi botnet is reminiscent of Mirai, an innovative IoT malware strain that emerged in the summer of 2016 and successfully out-competed virtually all other IoT malware strains in existence at the time.

As first revealed by KrebsOnSecurity in January 2017, the Mirai authors were two U.S. men who co-ran a DDoS mitigation service — even as they were selling far more lucrative DDoS-for-hire services using the most powerful botnet on the planet.

Less than a week after the Mirai botnet was used in a days-long DDoS against KrebsOnSecurity, the Mirai authors published the source code to their botnet so that they would not be the only ones in possession of it in the event of their arrest by federal investigators.

Ironically, the leaking of the Mirai source is precisely what led to the eventual unmasking and arrest of the Mirai authors, who went on to serve probation sentences that required them to consult with FBI investigators on DDoS investigations. But that leak also rapidly led to the creation of dozens of Mirai botnet clones, many of which were harnessed to fuel their own powerful DDoS-for-hire services.

Menscher told KrebsOnSecurity that as counterintuitive as it may sound, the Internet as a whole would probably be better off if the source code for Aisuru became public knowledge. After all, he said, the people behind Aisuru are in constant competition with other IoT botnet operators who are all striving to commandeer a finite number of vulnerable IoT devices globally.

Such a development would almost certainly cause a proliferation of Aisuru botnet clones, he said, but at least then the overall firepower from each individual botnet would be greatly diminished — or at least within range of the mitigation capabilities of most DDoS protection providers.

Barring a source code leak, Menscher said, it would be nice if someone published the full list of software exploits being used by the Aisuru operators to grow their botnet so quickly.

“Part of the reason Mirai was so dangerous was that it effectively took out competing botnets,” he said. “This attack somehow managed to compromise all these boxes that nobody else knows about. Ideally, we’d want to see that fragmented out, so that no [individual botnet operator] controls too much.”

Microsoft on Tuesday released software updates to fix at least 70 vulnerabilities in Windows and related products, including five zero-day flaws that are already seeing active exploitation. Adding to the sense of urgency with this month’s patch batch from Redmond are fixes for two other weaknesses that now have public proof-of-concept exploits available.

Microsoft and several security firms have disclosed that attackers are exploiting a pair of bugs in the Windows Common Log File System (CLFS) driver that allow attackers to elevate their privileges on a vulnerable device. The Windows CLFS is a critical Windows component responsible for logging services, and is widely used by Windows system services and third-party applications for logging. Tracked as CVE-2025-32701 & CVE-2025-32706, these flaws are present in all supported versions of Windows 10 and 11, as well as their server versions.

Kev Breen, senior director of threat research at Immersive Labs, said privilege escalation bugs assume an attacker already has initial access to a compromised host, typically through a phishing attack or by using stolen credentials. But if that access already exists, Breen said, attackers can gain access to the much more powerful Windows SYSTEM account, which can disable security tooling or even gain domain administration level permissions using credential harvesting tools.

“The patch notes don’t provide technical details on how this is being exploited, and no Indicators of Compromise (IOCs) are shared, meaning the only mitigation security teams have is to apply these patches immediately,” he said. “The average time from public disclosure to exploitation at scale is less than five days, with threat actors, ransomware groups, and affiliates quick to leverage these vulnerabilities.”

Two other zero-days patched by Microsoft today also were elevation of privilege flaws: CVE-2025-32709, which concerns afd.sys, the Windows Ancillary Function Driver that enables Windows applications to connect to the Internet; and CVE-2025-30400, a weakness in the Desktop Window Manager (DWM) library for Windows. As Adam Barnett at Rapid7 notes, tomorrow marks the one-year anniversary of CVE-2024-30051, a previous zero-day elevation of privilege vulnerability in this same DWM component.

The fifth zero-day patched today is CVE-2025-30397, a flaw in the Microsoft Scripting Engine, a key component used by Internet Explorer and Internet Explorer mode in Microsoft Edge.

Chris Goettl at Ivanti points out that the Windows 11 and Server 2025 updates include some new AI features that carry a lot of baggage and weigh in at around 4 gigabytes. Said baggage includes new artificial intelligence (AI) capabilities, including the controversial Recall feature, which constantly takes screenshots of what users are doing on Windows CoPilot-enabled computers.

Microsoft went back to the drawing board on Recall after a fountain of negative feedback from security experts, who warned it would present an attractive target and a potential gold mine for attackers. Microsoft appears to have made some efforts to prevent Recall from scooping up sensitive financial information, but privacy and security concerns still linger. Former Microsoftie Kevin Beaumont has a good teardown on Microsoft’s updates to Recall.

In any case, windowslatest.com reports that Windows 11 version 24H2 shows up ready for downloads, even if you don’t want it.

“It will now show up for ‘download and install’ automatically if you go to Settings > Windows Update and click Check for updates, but only when your device does not have a compatibility hold,” the publication reported. “Even if you don’t check for updates, Windows 11 24H2 will automatically download at some point.”

Apple users likely have their own patching to do. On May 12 Apple released security updates to fix at least 30 vulnerabilities in iOS and iPadOS (the updated version is 18.5). TechCrunch writes that iOS 18.5 also expands emergency satellite capabilities to iPhone 13 owners for the first time (previously it was only available on iPhone 14 or later).

Apple also released updates for macOS Sequoia, macOS Sonoma, macOS Ventura, WatchOS, tvOS and visionOS. Apple said there is no indication of active exploitation for any of the vulnerabilities fixed this month.

As always, please back up your device and/or important data before attempting any updates. And please feel free to sound off in the comments if you run into any problems applying any of these fixes.