Our first story of 2026 revealed how a destructive new botnet called Kimwolf has infected more than two million devices by mass-compromising a vast number of unofficial Android TV streaming boxes. Today, we’ll dig through digital clues left behind by the hackers, network operators and services that appear to have benefitted from Kimwolf’s spread.

On Dec. 17, 2025, the Chinese security firm XLab published a deep dive on Kimwolf, which forces infected devices to participate in distributed denial-of-service (DDoS) attacks and to relay abusive and malicious Internet traffic for so-called “residential proxy” services.

The software that turns one’s device into a residential proxy is often quietly bundled with mobile apps and games. Kimwolf specifically targeted residential proxy software that is factory installed on more than a thousand different models of unsanctioned Android TV streaming devices. Very quickly, the residential proxy’s Internet address starts funneling traffic that is linked to ad fraud, account takeover attempts and mass content scraping.

The XLab report explained its researchers found “definitive evidence” that the same cybercriminal actors and infrastructure were used to deploy both Kimwolf and the Aisuru botnet — an earlier version of Kimwolf that also enslaved devices for use in DDoS attacks and proxy services.

XLab said it suspected since October that Kimwolf and Aisuru had the same author(s) and operators, based in part on shared code changes over time. But it said those suspicions were confirmed on December 8 when it witnessed both botnet strains being distributed by the same Internet address at 93.95.112[.]59.

RESI RACK

Public records show the Internet address range flagged by XLab is assigned to Lehi, Utah-based Resi Rack LLC. Resi Rack’s website bills the company as a “Premium Game Server Hosting Provider.” Meanwhile, Resi Rack’s ads on the Internet moneymaking forum BlackHatWorld refer to it as a “Premium Residential Proxy Hosting and Proxy Software Solutions Company.”

Resi Rack co-founder Cassidy Hales told KrebsOnSecurity his company received a notification on December 10 about Kimwolf using their network “that detailed what was being done by one of our customers leasing our servers.”

“When we received this email we took care of this issue immediately,” Hales wrote in response to an email requesting comment. “This is something we are very disappointed is now associated with our name and this was not the intention of our company whatsoever.”

The Resi Rack Internet address cited by XLab on December 8 came onto KrebsOnSecurity’s radar more than two weeks before that. Benjamin Brundage is founder of Synthient, a startup that tracks proxy services. In late October 2025, Brundage shared that the people selling various proxy services which benefitted from the Aisuru and Kimwolf botnets were doing so at a new Discord server called resi[.]to.

When KrebsOnSecurity joined the resi[.]to Discord channel in late October as a silent lurker, the server had fewer than 150 members, including “Shox” — the nickname used by Resi Rack’s co-founder Mr. Hales — and his business partner “Linus,” who did not respond to requests for comment.

Other members of the resi[.]to Discord channel would periodically post new IP addresses that were responsible for proxying traffic over the Kimwolf botnet. As the screenshot from resi[.]to above shows, that Resi Rack Internet address flagged by XLab was used by Kimwolf to direct proxy traffic as far back as November 24, if not earlier. All told, Synthient said it tracked at least seven static Resi Rack IP addresses connected to Kimwolf proxy infrastructure between October and December 2025.

Neither of Resi Rack’s co-owners responded to follow-up questions. Both have been active in selling proxy services via Discord for nearly two years. According to a review of Discord messages indexed by the cyber intelligence firm Flashpoint, Shox and Linus spent much of 2024 selling static “ISP proxies” by routing various Internet address blocks at major U.S. Internet service providers.

In February 2025, AT&T announced that effective July 31, 2025, it would no longer originate routes for network blocks that are not owned and managed by AT&T (other major ISPs have since made similar moves). Less than a month later, Shox and Linus told customers they would soon cease offering static ISP proxies as a result of these policy changes.

DORT & SNOW

The stated owner of the resi[.]to Discord server went by the abbreviated username “D.” That initial appears to be short for the hacker handle “Dort,” a name that was invoked frequently throughout these Discord chats.

This “Dort” nickname came up in KrebsOnSecurity’s recent conversations with “Forky,” a Brazilian man who acknowledged being involved in the marketing of the Aisuru botnet at its inception in late 2024. But Forky vehemently denied having anything to do with a series of massive and record-smashing DDoS attacks in the latter half of 2025 that were blamed on Aisuru, saying the botnet by that point had been taken over by rivals.

Forky asserts that Dort is a resident of Canada and one of at least two individuals currently in control of the Aisuru/Kimwolf botnet. The other individual Forky named as an Aisuru/Kimwolf botmaster goes by the nickname “Snow.”

On January 2 — just hours after our story on Kimwolf was published — the historical chat records on resi[.]to were erased without warning and replaced by a profanity-laced message for Synthient’s founder. Minutes after that, the entire server disappeared.

Later that same day, several of the more active members of the now-defunct resi[.]to Discord server moved to a Telegram channel where they posted Brundage’s personal information, and generally complained about being unable to find reliable “bulletproof” hosting for their botnet.

Hilariously, a user by the name “Richard Remington” briefly appeared in the group’s Telegram server to post a crude “Happy New Year” sketch that claims Dort and Snow are now in control of 3.5 million devices infected by Aisuru and/or Kimwolf. Richard Remington’s Telegram account has since been deleted, but it previously stated its owner operates a website that caters to DDoS-for-hire or “stresser” services seeking to test their firepower.

BYTECONNECT, PLAINPROXIES, AND 3XK TECH

Reports from both Synthient and XLab found that Kimwolf was used to deploy programs that turned infected systems into Internet traffic relays for multiple residential proxy services. Among those was a component that installed a software development kit (SDK) called ByteConnect, which is distributed by a provider known as Plainproxies.

ByteConnect says it specializes in “monetizing apps ethically and free,” while Plainproxies advertises the ability to provide content scraping companies with “unlimited” proxy pools. However, Synthient said that upon connecting to ByteConnect’s SDK they instead observed a mass influx of credential-stuffing attacks targeting email servers and popular online websites.

A search on LinkedIn finds the CEO of Plainproxies is Friedrich Kraft, whose resume says he is co-founder of ByteConnect Ltd. Public Internet routing records show Mr. Kraft also operates a hosting firm in Germany called 3XK Tech GmbH. Mr. Kraft did not respond to repeated requests for an interview.

In July 2025, Cloudflare reported that 3XK Tech (a.k.a. Drei-K-Tech) had become the Internet’s largest source of application-layer DDoS attacks. In November 2025, the security firm GreyNoise Intelligence found that Internet addresses on 3XK Tech were responsible for roughly three-quarters of the Internet scanning being done at the time for a newly discovered and critical vulnerability in security products made by Palo Alto Networks.

LinkedIn has a profile for another Plainproxies employee, Julia Levi, who is listed as co-founder of ByteConnect. Ms. Levi did not respond to requests for comment. Her resume says she previously worked for two major proxy providers: Netnut Proxy Network, and Bright Data.

Synthient likewise said Plainproxies ignored their outreach, noting that the Byteconnect SDK continues to remain active on devices compromised by Kimwolf.

MASKIFY

Synthient’s January 2 report said another proxy provider heavily involved in the sale of Kimwolf proxies was Maskify, which currently advertises on multiple cybercrime forums that it has more than six million residential Internet addresses for rent.

Maskify prices its service at a rate of 30 cents per gigabyte of data relayed through their proxies. According to Synthient, that price range is insanely low and is far cheaper than any other proxy provider in business today.

“Synthient’s Research Team received screenshots from other proxy providers showing key Kimwolf actors attempting to offload proxy bandwidth in exchange for upfront cash,” the Synthient report noted. “This approach likely helped fuel early development, with associated members spending earnings on infrastructure and outsourced development tasks. Please note that resellers know precisely what they are selling; proxies at these prices are not ethically sourced.”

Maskify did not respond to requests for comment.

BOTMASTERS LASH OUT

Hours after our first Kimwolf story was published last week, the resi[.]to Discord server vanished, Synthient’s website was hit with a DDoS attack, and the Kimwolf botmasters took to doxing Brundage via their botnet.

The harassing messages appeared as text records uploaded to the Ethereum Name Service (ENS), a distributed system for supporting smart contracts deployed on the Ethereum blockchain. As documented by XLab, in mid-December the Kimwolf operators upgraded their infrastructure and began using ENS to better withstand the near-constant takedown efforts targeting the botnet’s control servers.

By telling infected systems to seek out the Kimwolf control servers via ENS, even if the servers that the botmasters use to control the botnet are taken down the attacker only needs to update the ENS text record to reflect the new Internet address of the control server, and the infected devices will immediately know where to look for further instructions.

“This channel itself relies on the decentralized nature of blockchain, unregulated by Ethereum or other blockchain operators, and cannot be blocked,” XLab wrote.

The text records included in Kimwolf’s ENS instructions can also feature short messages, such as those that carried Brundage’s personal information. Other ENS text records associated with Kimwolf offered some sage advice: “If flagged, we encourage the TV box to be destroyed.”

Both Synthient and XLabs say Kimwolf targets a vast number of Android TV streaming box models, all of which have zero security protections, and many of which ship with proxy malware built in. Generally speaking, if you can send a data packet to one of these devices you can also seize administrative control over it.

If you own a TV box that matches one of these model names and/or numbers, please just rip it out of your network. If you encounter one of these devices on the network of a family member or friend, send them a link to this story (or to our January 2 story on Kimwolf) and explain that it’s not worth the potential hassle and harm created by keeping them plugged in.

KrebsOnSecurity.com celebrates its 16th anniversary today! A huge “thank you” to all of our readers — newcomers, long-timers and drive-by critics alike. Your engagement this past year here has been tremendous and truly a salve on a handful of dark days. Happily, comeuppance was a strong theme running through our coverage in 2025, with a primary focus on entities that enabled complex and globally-dispersed cybercrime services.

In May 2024, we scrutinized the history and ownership of Stark Industries Solutions Ltd., a “bulletproof hosting” provider that came online just two weeks before Russia invaded Ukraine and served as a primary staging ground for repeated Kremlin cyberattacks and disinformation efforts. A year later, Stark and its two co-owners were sanctioned by the European Union, but our analysis showed those penalties have done little to stop the Stark proprietors from rebranding and transferring considerable network assets to other entities they control.

In December 2024, KrebsOnSecurity profiled Cryptomus, a financial firm registered in Canada that emerged as the payment processor of choice for dozens of Russian cryptocurrency exchanges and websites hawking cybercrime services aimed at Russian-speaking customers. In October 2025, Canadian financial regulators ruled that Cryptomus had grossly violated its anti-money laundering laws, and levied a record $176 million fine against the platform.

In September 2023, KrebsOnSecurity published findings from researchers who concluded that a series of six-figure cyberheists across dozens of victims resulted from thieves cracking master passwords stolen from the password manager service LastPass in 2022. In a court filing in March 2025, U.S. federal agents investigating a spectacular $150 million cryptocurrency heist said they had reached the same conclusion.

Phishing was a major theme of this year’s coverage, which peered inside the day-to-day operations of several voice phishing gangs that routinely carried out elaborate, convincing, and financially devastating cryptocurrency thefts. A Day in the Life of a Prolific Voice Phishing Crew examined how one cybercrime gang abused legitimate services at Apple and Google to force a variety of outbound communications to their users, including emails, automated phone calls and system-level messages sent to all signed-in devices.

Nearly a half-dozen stories in 2025 dissected the incessant SMS phishing or “smishing” coming from China-based phishing kit vendors, who make it easy for customers to convert phished payment card data into mobile wallets from Apple and Google. In an effort to wrest control over this phishing syndicate’s online resources, Google has since filed at least two John Doe lawsuits targeting these groups and dozens of unnamed defendants.

In January, we highlighted research into a dodgy and sprawling content delivery network called Funnull that specialized in helping China-based gambling and money laundering websites distribute their operations across multiple U.S.-based cloud providers. Five months later, the U.S. government sanctioned Funnull, identifying it as a top source of investment/romance scams known as “pig butchering.”

In May, Pakistan arrested 21 people alleged to be working for Heartsender, a phishing and malware dissemination service that KrebsOnSecurity first profiled back in 2015. The arrests came shortly after the FBI and the Dutch police seized dozens of servers and domains for the group. Many of those arrested were first publicly identified in a 2021 story here about how they’d inadvertently infected their computers with malware that gave away their real-life identities.

In April, the U.S. Department of Justice indicted the proprietors of a Pakistan-based e-commerce company for conspiring to distribute synthetic opioids in the United States. The following month, KrebsOnSecurity detailed how the proprietors of the sanctioned entity are perhaps better known for operating an elaborate and lengthy scheme to scam westerners seeking help with trademarks, book writing, mobile app development and logo designs.

Earlier this month, we examined an academic cheating empire turbocharged by Google Ads that earned tens of millions of dollars in revenue and has curious ties to a Kremlin-connected oligarch whose Russian university builds drones for Russia’s war against Ukraine.

As ever, KrebsOnSecurity endeavored to keep close tabs on the world’s biggest and most disruptive botnets, which pummeled the Internet this year with distributed denial-of-service (DDoS) assaults that were two to three times the size and impact of previous record DDoS attacks.

In June, KrebsOnSecurity.com was hit by the largest DDoS attack that Google had ever mitigated at the time (we are a grateful guest of Google’s excellent Project Shield offering). Experts blamed that attack on an Internet-of-Things botnet called Aisuru that had rapidly grown in size and firepower since its debut in late 2024. Another Aisuru attack on Cloudflare just days later practically doubled the size of the June attack against this website. Not long after that, Aisuru was blamed for a DDoS that again doubled the previous record.

In October, it appeared the cybercriminals in control of Aisuru had shifted the botnet’s focus from DDoS to a more sustainable and profitable use: Renting hundreds of thousands of infected Internet of Things (IoT) devices to proxy services that help cybercriminals anonymize their traffic.

However, it has recently become clear that at least some of the disruptive botnet and residential proxy activity attributed to Aisuru last year likely was the work of people responsible for building and testing a powerful botnet known as Kimwolf. Chinese security firm XLab, which was the first to chronicle Aisuru’s rise in 2024, recently profiled Kimwolf as easily the world’s biggest and most dangerous collection of compromised machines — with approximately 1.83 million devices under its thumb as of December 17.

XLab noted that the Kimwolf author “shows an almost ‘obsessive’ fixation on the well-known cybersecurity investigative journalist Brian Krebs, leaving easter eggs related to him in multiple places.”

I am happy to report that the first KrebsOnSecurity stories of 2026 will go deep into the origins of Kimwolf, and examine the botnet’s unique and highly invasive means of spreading digital disease far and wide. The first in that series will include a somewhat sobering and global security notification concerning the devices and residential proxy services that are inadvertently helping to power Kimwolf’s rapid growth.

Thank you once again for your continued readership, encouragement and support. If you like the content we publish at KrebsOnSecurity.com, please consider making an exception for our domain in your ad blocker. The ads we run are limited to a handful of static images that are all served in-house and vetted by me (there is no third-party content on this site, period). Doing so would help further support the work you see here almost every week.

And if you haven’t done so yet, sign up for our email newsletter! (62,000 other subscribers can’t be wrong, right?). The newsletter is just a plain text email that goes out the moment a new story is published. We send between one and two emails a week, we never share our email list, and we don’t run surveys or promotions.

Thanks again, and Happy New Year everyone! Be safe out there.

In March 2024, Mozilla said it was winding down its collaboration with Onerep — an identity protection service offered with the Firefox web browser that promises to remove users from hundreds of people-search sites — after KrebsOnSecurity revealed Onerep’s founder had created dozens of people-search services and was continuing to operate at least one of them. Sixteen months later, however, Mozilla is still promoting Onerep. This week, Mozilla announced its partnership with Onerep will officially end next month.

In a statement published Tuesday, Mozilla said it will soon discontinue Monitor Plus, which offered data broker site scans and automated personal data removal from Onerep.

“We will continue to offer our free Monitor data breach service, which is integrated into Firefox’s credential manager, and we are focused on integrating more of our privacy and security experiences in Firefox, including our VPN, for free,” the advisory reads.

Mozilla said current Monitor Plus subscribers will retain full access through the wind-down period, which ends on Dec. 17, 2025. After that, those subscribers will automatically receive a prorated refund for the unused portion of their subscription.

“We explored several options to keep Monitor Plus going, but our high standards for vendors, and the realities of the data broker ecosystem made it challenging to consistently deliver the level of value and reliability we expect for our users,” Mozilla statement reads.

On March 14, 2024, KrebsOnSecurity published an investigation showing that Onerep’s Belarusian CEO and founder Dimitiri Shelest launched dozens of people-search services since 2010, including a still-active data broker called Nuwber that sells background reports on people. Shelest released a lengthy statement wherein he acknowledged maintaining an ownership stake in Nuwber, a data broker he founded in 2015 — around the same time he launched Onerep.

A Ukrainian man indicted in 2012 for conspiring with a prolific hacking group to steal tens of millions of dollars from U.S. businesses was arrested in Italy and is now in custody in the United States, KrebsOnSecurity has learned.

Sources close to the investigation say Yuriy Igorevich Rybtsov, a 41-year-old from the Russia-controlled city of Donetsk, Ukraine, was previously referenced in U.S. federal charging documents only by his online handle “MrICQ.” According to a 13-year-old indictment (PDF) filed by prosecutors in Nebraska, MrICQ was a developer for a cybercrime group known as “Jabber Zeus.”

The Jabber Zeus name is derived from the malware they used — a custom version of the ZeuS banking trojan — that stole banking login credentials and would send the group a Jabber instant message each time a new victim entered a one-time passcode at a financial institution website. The gang targeted mostly small to mid-sized businesses, and they were an early pioneer of so-called “man-in-the-browser” attacks, malware that can silently intercept any data that victims submit in a web-based form.

Once inside a victim company’s accounts, the Jabber Zeus crew would modify the firm’s payroll to add dozens of “money mules,” people recruited through elaborate work-at-home schemes to handle bank transfers. The mules in turn would forward any stolen payroll deposits — minus their commissions — via wire transfers to other mules in Ukraine and the United Kingdom.

The 2012 indictment targeting the Jabber Zeus crew named MrICQ as “John Doe #3,” and said this person handled incoming notifications of newly compromised victims. The Department of Justice (DOJ) said MrICQ also helped the group launder the proceeds of their heists through electronic currency exchange services.

Two sources familiar with the Jabber Zeus investigation said Rybtsov was arrested in Italy, although the exact date and circumstances of his arrest remain unclear. A summary of recent decisions (PDF) published by the Italian Supreme Court states that in April 2025, Rybtsov lost a final appeal to avoid extradition to the United States.

According to the mugshot website lockedup[.]wtf, Rybtsov arrived in Nebraska on October 9, and was being held under an arrest warrant from the U.S. Federal Bureau of Investigation (FBI).

The data breach tracking service Constella Intelligence found breached records from the business profiling site bvdinfo[.]com showing that a 41-year-old Yuriy Igorevich Rybtsov worked in a building at 59 Barnaulska St. in Donetsk. Further searching on this address in Constella finds the same apartment building was shared by a business registered to Vyacheslav “Tank” Penchukov, the leader of the Jabber Zeus crew in Ukraine.

Penchukov was arrested in 2022 while traveling to meet his wife in Switzerland. Last year, a federal court in Nebraska sentenced Penchukov to 18 years in prison and ordered him to pay more than $73 million in restitution.

Lawrence Baldwin is founder of myNetWatchman, a threat intelligence company based in Georgia that began tracking and disrupting the Jabber Zeus gang in 2009. myNetWatchman had secretly gained access to the Jabber chat server used by the Ukrainian hackers, allowing Baldwin to eavesdrop on the daily conversations between MrICQ and other Jabber Zeus members.

Baldwin shared those real-time chat records with multiple state and federal law enforcement agencies, and with this reporter. Between 2010 and 2013, I spent several hours each day alerting small businesses across the country that their payroll accounts were about to be drained by these cybercriminals.

Those notifications, and Baldwin’s tireless efforts, saved countless would-be victims a great deal of money. In most cases, however, we were already too late. Nevertheless, the pilfered Jabber Zeus group chats provided the basis for dozens of stories published here about small businesses fighting their banks in court over six- and seven-figure financial losses.

Baldwin said the Jabber Zeus crew was far ahead of its peers in several respects. For starters, their intercepted chats showed they worked to create a highly customized botnet directly with the author of the original Zeus Trojan — Evgeniy Mikhailovich Bogachev, a Russian man who has long been on the FBI’s “Most Wanted” list. The feds have a standing $3 million reward for information leading to Bogachev’s arrest.

The core innovation of Jabber Zeus was an alert that MrICQ would receive each time a new victim entered a one-time password code into a phishing page mimicking their financial institution. The gang’s internal name for this component was “Leprechaun,” (the video below from myNetWatchman shows it in action). Jabber Zeus would actually re-write the HTML code as displayed in the victim’s browser, allowing them to intercept any passcodes sent by the victim’s bank for multi-factor authentication.

“These guys had compromised such a large number of victims that they were getting buried in a tsunami of stolen banking credentials,” Baldwin told KrebsOnSecurity. “But the whole point of Leprechaun was to isolate the highest-value credentials — the commercial bank accounts with two-factor authentication turned on. They knew these were far juicier targets because they clearly had a lot more money to protect.”

Baldwin said the Jabber Zeus trojan also included a custom “backconnect” component that allowed the hackers to relay their bank account takeovers through the victim’s own infected PC.

“The Jabber Zeus crew were literally connecting to the victim’s bank account from the victim’s IP address, or from the remote control function and by fully emulating the device,” he said. “That trojan was like a hot knife through butter of what everyone thought was state-of-the-art secure online banking at the time.”

Although the Jabber Zeus crew was in direct contact with the Zeus author, the chats intercepted by myNetWatchman show Bogachev frequently ignored the group’s pleas for help. The government says the real leader of the Jabber Zeus crew was Maksim Yakubets, a 38-year Ukrainian man with Russian citizenship who went by the hacker handle “Aqua.”

The Jabber chats intercepted by Baldwin show that Aqua interacted almost daily with MrICQ, Tank and other members of the hacking team, often facilitating the group’s money mule and cashout activities remotely from Russia.

The government says Yakubets/Aqua would later emerge as the leader of an elite cybercrime ring of at least 17 hackers that referred to themselves internally as “Evil Corp.” Members of Evil Corp developed and used the Dridex (a.k.a. Bugat) trojan, which helped them siphon more than $100 million from hundreds of victim companies in the United States and Europe.

This 2019 story about the government’s $5 million bounty for information leading to Yakubets’s arrest includes excerpts of conversations between Aqua, Tank, Bogachev and other Jabber Zeus crew members discussing stories I’d written about their victims. Both Baldwin and I were interviewed at length for a new weekly six-part podcast by the BBC that delves deep into the history of Evil Corp. Episode One focuses on the evolution of Zeus, while the second episode centers on an investigation into the group by former FBI agent Jim Craig.

Aisuru, the botnet responsible for a series of record-smashing distributed denial-of-service (DDoS) attacks this year, recently was overhauled to support a more low-key, lucrative and sustainable business: Renting hundreds of thousands of infected Internet of Things (IoT) devices to proxy services that help cybercriminals anonymize their traffic. Experts say a glut of proxies from Aisuru and other sources is fueling large-scale data harvesting efforts tied to various artificial intelligence (AI) projects, helping content scrapers evade detection by routing their traffic through residential connections that appear to be regular Internet users.

First identified in August 2024, Aisuru has spread to at least 700,000 IoT systems, such as poorly secured Internet routers and security cameras. Aisuru’s overlords have used their massive botnet to clobber targets with headline-grabbing DDoS attacks, flooding targeted hosts with blasts of junk requests from all infected systems simultaneously.

In June, Aisuru hit KrebsOnSecurity.com with a DDoS clocking at 6.3 terabits per second — the biggest attack that Google had ever mitigated at the time. In the weeks and months that followed, Aisuru’s operators demonstrated DDoS capabilities of nearly 30 terabits of data per second — well beyond the attack mitigation capabilities of most Internet destinations.

These digital sieges have been particularly disruptive this year for U.S.-based Internet service providers (ISPs), in part because Aisuru recently succeeded in taking over a large number of IoT devices in the United States. And when Aisuru launches attacks, the volume of outgoing traffic from infected systems on these ISPs is often so high that it can disrupt or degrade Internet service for adjacent (non-botted) customers of the ISPs.

“Multiple broadband access network operators have experienced significant operational impact due to outbound DDoS attacks in excess of 1.5Tb/sec launched from Aisuru botnet nodes residing on end-customer premises,” wrote Roland Dobbins, principal engineer at Netscout, in a recent executive summary on Aisuru. “Outbound/crossbound attack traffic exceeding 1Tb/sec from compromised customer premise equipment (CPE) devices has caused significant disruption to wireline and wireless broadband access networks. High-throughput attacks have caused chassis-based router line card failures.”

The incessant attacks from Aisuru have caught the attention of federal authorities in the United States and Europe (many of Aisuru’s victims are customers of ISPs and hosting providers based in Europe). Quite recently, some of the world’s largest ISPs have started informally sharing block lists identifying the rapidly shifting locations of the servers that the attackers use to control the activities of the botnet.

Experts say the Aisuru botmasters recently updated their malware so that compromised devices can more easily be rented to so-called “residential proxy” providers. These proxy services allow paying customers to route their Internet communications through someone else’s device, providing anonymity and the ability to appear as a regular Internet user in almost any major city worldwide.

From a website’s perspective, the IP traffic of a residential proxy network user appears to originate from the rented residential IP address, not from the proxy service customer. Proxy services can be used in a legitimate manner for several business purposes — such as price comparisons or sales intelligence. But they are massively abused for hiding cybercrime activity (think advertising fraud, credential stuffing) because they can make it difficult to trace malicious traffic to its original source.

And as we’ll see in a moment, this entire shadowy industry appears to be shifting its focus toward enabling aggressive content scraping activity that continuously feeds raw data into large language models (LLMs) built to support various AI projects.

‘INSANE’ GROWTH

Riley Kilmer is co-founder of spur.us, a service that tracks proxy networks. Kilmer said all of the top proxy services have grown substantially over the past six months.

“I just checked, and in the last 90 days we’ve seen 250 million unique residential proxy IPs,” Kilmer said. “That is insane. That is so high of a number, it’s unheard of. These proxies are absolutely everywhere now.”

Today, Spur says it is tracking an unprecedented spike in available proxies across all providers, including;

LUMINATI_PROXY    11,856,421
NETNUT_PROXY    10,982,458
ABCPROXY_PROXY    9,294,419
OXYLABS_PROXY     6,754,790
IPIDEA_PROXY     3,209,313
EARNFM_PROXY    2,659,913
NODEMAVEN_PROXY    2,627,851
INFATICA_PROXY    2,335,194
IPROYAL_PROXY    2,032,027
YILU_PROXY    1,549,155

Reached for comment about the apparent rapid growth in their proxy network, Oxylabs (#4 on Spur’s list) said while their proxy pool did grow recently, it did so at nowhere near the rate cited by Spur.

“We don’t systematically track other providers’ figures, and we’re not aware of any instances of 10× or 100× growth, especially when it comes to a few bigger companies that are legitimate businesses,” the company said in a written statement.

Bright Data was formerly known as Luminati Networks, the name that is currently at the top of Spur’s list of the biggest residential proxy networks. Bright Data likewise told KrebsOnSecurity that Spur’s current estimates of its proxy network are dramatically overstated and inaccurate.

“We did not actively initiate nor do we see any 10x or 100x expansion of our network, which leads me to believe that someone might be presenting these IPs as Bright Data’s in some way,” said Rony Shalit, Bright Data’s chief compliance and ethics officer. “In many cases in the past, due to us being the leading data collection proxy provider, IPs were falsely tagged as being part of our network, or while being used by other proxy providers for malicious activity.”

“Our network is only sourced from verified IP providers and a robust opt-in only residential peers, which we work hard and in complete transparency to obtain,” Shalit continued. “Every DC, ISP or SDK partner is reviewed and approved, and every residential peer must actively opt in to be part of our network.”

HK NETWORK

Even Spur acknowledges that Luminati and Oxylabs are unlike most other proxy services on their top proxy providers list, in that these providers actually adhere to “know-your-customer” policies, such as requiring video calls with all customers, and strictly blocking customers from reselling access.

Benjamin Brundage is founder of Synthient, a startup that helps companies detect proxy networks. Brundage said if there is increasing confusion around which proxy networks are the most worrisome, it’s because nearly all of these lesser-known proxy services have evolved into highly incestuous bandwidth resellers. What’s more, he said, some proxy providers do not appreciate being tracked and have been known to take aggressive steps to confuse systems that scan the Internet for residential proxy nodes.

Brundage said most proxy services today have created their own software development kit or SDK that other app developers can bundle with their code to earn revenue. These SDKs quietly modify the user’s device so that some portion of their bandwidth can be used to forward traffic from proxy service customers.

“Proxy providers have pools of constantly churning IP addresses,” he said. “These IP addresses are sourced through various means, such as bandwidth-sharing apps, botnets, Android SDKs, and more. These providers will often either directly approach resellers or offer a reseller program that allows users to resell bandwidth through their platform.”

Many SDK providers say they require full consent before allowing their software to be installed on end-user devices. Still, those opt-in agreements and consent checkboxes may be little more than a formality for cybercriminals like the Aisuru botmasters, who can earn a commission each time one of their infected devices is forced to install some SDK that enables one or more of these proxy services.

Depending on its structure, a single provider may operate hundreds of different proxy pools at a time — all maintained through other means, Brundage said.

“Often, you’ll see resellers maintaining their own proxy pool in addition to an upstream provider,” he said. “It allows them to market a proxy pool to high-value clients and offer an unlimited bandwidth plan for cheap reduce their own costs.”

Some proxy providers appear to be directly in league with botmasters. Brundage identified one proxy seller that was aggressively advertising cheap and plentiful bandwidth to content scraping companies. After scanning that provider’s pool of available proxies, Brundage said he found a one-to-one match with IP addresses he’d previously mapped to the Aisuru botnet.

Brundage says that by almost any measurement, the world’s largest residential proxy service is IPidea, a China-based proxy network. IPidea is #5 on Spur’s Top 10, and Brundage said its brands include ABCProxy (#3), Roxlabs, LunaProxy, PIA S5 Proxy, PyProxy, 922Proxy, 360Proxy, IP2World, and Cherry Proxy. Spur’s Kilmer said they also track Yilu Proxy (#10) as IPidea.

Brundage said all of these providers operate under a corporate umbrella known on the cybercrime forums as “HK Network.”

“The way it works is there’s this whole reseller ecosystem, where IPidea will be incredibly aggressive and approach all these proxy providers with the offer, ‘Hey, if you guys buy bandwidth from us, we’ll give you these amazing reseller prices,'” Brundage explained. “But they’re also very aggressive in recruiting resellers for their apps.”

Those apps include a range of low-cost and “free” virtual private networking (VPN) services that indeed allow users to enjoy a free VPN, but which also turn the user’s device into a traffic relay that can be rented to cybercriminals, or else parceled out to countless other proxy networks.

“They have all this bandwidth to offload,” Brundage said of IPidea and its sister networks. “And they can do it through their own platforms, or they go get resellers to do it for them by advertising on sketchy hacker forums to reach more people.”

One of IPidea’s core brands is 922S5Proxy, which is a not-so-subtle nod to the 911S5Proxy service that was hugely popular between 2015 and 2022. In July 2022, KrebsOnSecurity published a deep dive into 911S5Proxy’s origins and apparent owners in China. Less than a week later, 911S5Proxy announced it was closing down after the company’s servers were massively hacked.

That 2022 story named Yunhe Wang from Beijing as the apparent owner and/or manager of the 911S5 proxy service. In May 2024, the U.S. Department of Justice arrested Mr Wang, alleging that his network was used to steal billions of dollars from financial institutions, credit card issuers, and federal lending programs. At the same time, the U.S. Treasury Department announced sanctions against Wang and two other Chinese nationals for operating 911S5Proxy.

DATA SCRAPING FOR AI

In recent months, multiple experts who track botnet and proxy activity have shared that a great deal of content scraping which ultimately benefits AI companies is now leveraging these proxy networks to further obfuscate their aggressive data-slurping activity. That’s because by routing it through residential IP addresses, content scraping firms can make their traffic far trickier to filter out.

“It’s really difficult to block, because there’s a risk of blocking real people,” Spur’s Kilmer said of the LLM scraping activity that is fed through individual residential IP addresses, which are often shared by multiple customers at once.

Kilmer says the AI industry has brought a veneer of legitimacy to residential proxy business, which has heretofore mostly been associated with sketchy affiliate money making programs, automated abuse, and unwanted Internet traffic.

“Web crawling and scraping has always been a thing, but AI made it like a commodity, data that had to be collected,” Kilmer said. “Everybody wanted to monetize their own data pots, and how they monetize that is different across the board.”

Kilmer said many LLM-related scrapers rely on residential proxies in cases where the content provider has restricted access to their platform in some way, such as forcing interaction through an app, or keeping all content behind a login page with multi-factor authentication.

“Where the cost of data is out of reach — there is some exclusivity or reason they can’t access the data — they’ll turn to residential proxies so they look like a real person accessing that data,” Kilmer said of the content scraping efforts.

Aggressive AI crawlers increasingly are overloading community-maintained infrastructure, causing what amounts to persistent DDoS attacks on vital public resources. A report earlier this year from LibreNews found some open-source projects now see as much as 97 percent of their traffic originating from AI company bots, dramatically increasing bandwidth costs, service instability, and burdening already stretched-thin maintainers.

Cloudflare is now experimenting with tools that will allow content creators to charge a fee to AI crawlers to scrape their websites. The company’s “pay-per-crawl” feature is currently in a private beta, and it lets publishers set their own prices that bots must pay before scraping content.

On October 22, the social media and news network Reddit sued Oxylabs (PDF) and several other proxy providers, alleging that their systems enabled the mass-scraping of Reddit user content even though Reddit had taken steps to block such activity.

“Recognizing that Reddit denies scrapers like them access to its site, Defendants scrape the data from Google’s search results instead,” the lawsuit alleges. “They do so by masking their identities, hiding their locations, and disguising their web scrapers as regular people (among other techniques) to circumvent or bypass the security restrictions meant to stop them.”

Denas Grybauskas, chief governance and strategy officer at Oxylabs, said the company was shocked and disappointed by the lawsuit.

“Reddit has made no attempt to speak with us directly or communicate any potential concerns,” Grybauskas said in a written statement. “Oxylabs has always been and will continue to be a pioneer and an industry leader in public data collection, and it will not hesitate to defend itself against these allegations. Oxylabs’ position is that no company should claim ownership of public data that does not belong to them. It is possible that it is just an attempt to sell the same public data at an inflated price.”

As big and powerful as Aisuru may be, it is hardly the only botnet that is contributing to the overall broad availability of residential proxies. For example, on June 5 the FBI’s Internet Crime Complaint Center warned that an IoT malware threat dubbed BADBOX 2.0 had compromised millions of smart-TV boxes, digital projectors, vehicle infotainment units, picture frames, and other IoT devices.

In July, Google filed a lawsuit in New York federal court against the Badbox botnet’s alleged perpetrators. Google said the Badbox 2.0 botnet “compromised more than 10 million uncertified devices running Android’s open-source software, which lacks Google’s security protections. Cybercriminals infected these devices with pre-installed malware and exploited them to conduct large-scale ad fraud and other digital crimes.”

A FAMILIAR DOMAIN NAME

Brundage said the Aisuru botmasters have their own SDK, and for some reason part of its code tells many newly-infected systems to query the domain name fuckbriankrebs[.]com. This may be little more than an elaborate “screw you” to this site’s author: One of the botnet’s alleged partners goes by the handle “Forky,” and was identified in June by KrebsOnSecurity as a young man from Sao Paulo, Brazil.

Brundage noted that only systems infected with Aisuru’s Android SDK will be forced to resolve the domain. Initially, there was some discussion about whether the domain might have some utility as a “kill switch” capable of disrupting the botnet’s operations, although Brundage and others interviewed for this story say that is unlikely.

For one thing, they said, if the domain was somehow critical to the operation of the botnet, why was it still unregistered and actively for-sale? Why indeed, we asked. Happily, the domain name was deftly snatched up last week by Philippe Caturegli, “chief hacking officer” for the security intelligence company Seralys.

Caturegli enabled a passive DNS server on that domain and within a few hours received more than 700,000 requests for unique subdomains on fuckbriankrebs[.]com.

But even with that visibility into Aisuru, it is difficult to use this domain check-in feature to measure its true size, Brundage said. After all, he said, the systems that are phoning home to the domain are only a small portion of the overall botnet.

“The bots are hardcoded to just spam lookups on the subdomains,” he said. “So anytime an infection occurs or it runs in the background, it will do one of those DNS queries.”

The domain fuckbriankrebs[.]com has a storied history. On its initial launch in 2009, it was used to spread malicious software by the Cutwail spam botnet. In 2011, the domain was involved in a notable DDoS against this website from a botnet powered by Russkill (a.k.a. “Dirt Jumper”).

Domaintools.com finds that in 2015, fuckbriankrebs[.]com was registered to an email address attributed to David “Abdilo” Crees, a 27-year-old Australian man sentenced in May 2025 to time served for cybercrime convictions related to the Lizard Squad hacking group.

Update, Nov. 1, 2025, 10:25 a.m. ET: An earlier version of this story erroneously cited Spur’s proxy numbers from earlier this year; Spur said those numbers conflated residential proxies — which are rotating and attached to real end-user devices — with “ISP proxies” located at AT&T. ISP proxies, Spur said, involve tricking an ISP into routing a large number of IP addresses that are resold as far more static datacenter proxies.

Financial regulators in Canada this week levied $176 million in fines against Cryptomus, a digital payments platform that supports dozens of Russian cryptocurrency exchanges and websites hawking cybercrime services. The penalties for violating Canada’s anti money-laundering laws come ten months after KrebsOnSecurity noted that Cryptomus’s Vancouver street address was home to dozens of foreign currency dealers, money transfer businesses, and cryptocurrency exchanges — none of which were physically located there.

On October 16, the Financial Transactions and Reports Analysis Center of Canada (FINTRAC) imposed a $176,960,190 penalty on Xeltox Enterprises Ltd., more commonly known as the cryptocurrency payments platform Cryptomus.

FINTRAC found that Cryptomus failed to submit suspicious transaction reports in cases where there were reasonable grounds to suspect that they were related to the laundering of proceeds connected to trafficking in child sexual abuse material, fraud, ransomware payments and sanctions evasion.

“Given that numerous violations in this case were connected to trafficking in child sexual abuse material, fraud, ransomware payments and sanctions evasion, FINTRAC was compelled to take this unprecedented enforcement action,” said Sarah Paquet, director and CEO at the regulatory agency.

In December 2024, KrebsOnSecurity covered research by blockchain analyst and investigator Richard Sanders, who’d spent several months signing up for various cybercrime services, and then tracking where their customer funds go from there. The 122 services targeted in Sanders’s research all used Cryptomus, and included some of the more prominent businesses advertising on the cybercrime forums, such as:

-abuse-friendly or “bulletproof” hosting providers like anonvm[.]wtf, and PQHosting;
-sites selling aged email, financial, or social media accounts, such as verif[.]work and kopeechka[.]store;
-anonymity or “proxy” providers like crazyrdp[.]com and rdp[.]monster;
-anonymous SMS services, including anonsim[.]net and smsboss[.]pro.

Sanders found at least 56 cryptocurrency exchanges were using Cryptomus to process transactions, including financial entities with names like casher[.]su, grumbot[.]com, flymoney[.]biz, obama[.]ru and swop[.]is.

“These platforms were built for Russian speakers, and they each advertised the ability to anonymously swap one form of cryptocurrency for another,” the December 2024 story noted. “They also allowed the exchange of cryptocurrency for cash in accounts at some of Russia’s largest banks — nearly all of which are currently sanctioned by the United States and other western nations.”

Reached for comment on FINTRAC’s action, Sanders told KrebsOnSecurity he was surprised it took them so long.

“I have no idea why they don’t just sanction them or prosecute them,” Sanders said. “I’m not let down with the fine amount but it’s also just going to be the cost of doing business to them.”

The $173 million fine is a significant sum for FINTRAC, which imposed 23 such penalties last year totaling less than $26 million. But Sanders says FINTRAC still has much work to do in pursuing other shadowy money service businesses (MSBs) that are registered in Canada but are likely money laundering fronts for entities based in Russia and Iran.

In an investigation published in July 2024, CTV National News and the Investigative Journalism Foundation (IJF) documented dozens of cases across Canada where multiple MSBs are incorporated at the same address, often without the knowledge or consent of the location’s actual occupant.

Their inquiry found that the street address for Cryptomus parent Xeltox Enterprises was listed as the home of at least 76 foreign currency dealers, eight MSBs, and six cryptocurrency exchanges. At that address is a three-story building that used to be a bank and now houses a massage therapy clinic and a co-working space. But the news outlets found none of the MSBs or currency dealers were paying for services at that co-working space.

The reporters also found another collection of 97 MSBs clustered at an address for a commercial office suite in Ontario, even though there was no evidence any of these companies had ever arranged for any business services at that address.