Threat intelligence professionals have a sense of foreboding about a maximum-severity vulnerability Forta disclosed last week in its file-transfer service GoAnywhere MFT, as they steel themselves for active exploitation and signs of compromise.

Forta has not declared the defect actively exploited and did not answer questions to that effect from CyberScoop. Yet, researchers at watchTowr said they’ve obtained credible evidence of active exploitation of the vulnerability dating back to Sept. 10. 

The disagreement between vendor and research firm highlights a stubborn conundrum in the world of vulnerability disclosure and management. When defects turn out to be more severe  and actively exploited than vendors initially report, it creates unnecessary challenges for defenders and impacted users.

Forta did not answer questions about or respond to watchTowr’s latest findings. Forta maintains it discovered the vulnerability or its potential impact during a “security check” on Sept. 11, but it hasn’t included those details in the advisory. 

The cybersecurity vendor previously updated its security advisory for the deserialization vulnerability — CVE-2025-10035 — with details that baffled some researchers due to its lack of clarity. Forta added indicators of compromise and stack traces that, if present in customers’ log files, indicate their “instance was likely affected by this vulnerability,” the company said.

Ben Harris, founder and CEO at watchTowr, discredited some of Forta’s public statements about the vulnerability as he and his team of researchers confirmed suspicions they had about attacks linked to the vulnerability when it was first disclosed.

“What a mess,” he told CyberScoop. “All they had to do was just be honest and transparent — and instead, have turned this into scandal.”

Threat hunters’ concerns about the vulnerability were amplified when Forta updated its advisory to share specific strings for customers to monitor in their log files. 

The IOCs added to Forta’s advisory “makes us logically uneasy because it strongly suggests that attackers may already be active,” Harris said prior to confirming active exploitation. The details added to the vendor’s “Am I Impacted?” section in the advisory “implies this isn’t just a hypothetical risk,” Harris added. 

Researchers from Rapid7 and VulnCheck drew similar conclusions, noting its rare for vendors to publish IOCs for new critical vulnerabilities absent confirmed exploitation. 

“While the IOCs do not confirm exploitation in the wild, they strongly suggest the vendor believes that this vulnerability will be exploited if it has not already been,” said Stephen Fewer, senior principal researcher at Rapid7.

Private key, the missing link

Vulnerability researchers uncovered additional details about the steps attackers would have to take to achieve exploitation, including unexplained access to a specific private key.

“To successfully achieve remote-code execution, an attacker must send a signed Java object to the target GoAnywhere MFT server. The target server will use a public key to verify the signed object and, if the signature is valid, then an unsafe deserialization vulnerability can be hit, achieving arbitrary code execution,” Fewer said. 

“The missing detail is how the attacker can achieve this when the required private key is not present in the code base of GoAnywhere MFT,” he added.

This key, its whereabouts and how an attacker might gain access to it has researchers on edge, leading some to speculate the private key may have been leaked or otherwise stolen from a cloud-based GoAnywhere license server, which is designed to legitimize signed objects.

Researchers don’t have the private key and have been unable to produce a working exploit without it.

“Adversaries overall are opportunistic,” said Caitlin Condon, vice president of security research at VulnCheck. “It’s a pretty big deal for them to somehow get access to private keys.”

Cybercriminals have accessed private keys before, as evidenced earlier this month when an attacker exploited a zero-day vulnerability in Sitecore by using sample keys customers copied and pasted from the vendor’s documentation. 

A key was at the root cause of a major China-affiliated espionage attack on Microsoft Exchange Online in 2023, which exposed emails belonging to high-ranking U.S. government officials and others. Microsoft never definitively determined how the threat group it tracks as Storm-0558 acquired the key, and a federal review board later lambasted the company for “a cascade of security failures” in a scathing report about the attack and its widespread impact.

Vendor responsibility tested

Vendors are responsible for providing their customers with timely and actionable information that can protect them against attacks, including explicit acknowledgement of active exploitation, experts said. 

“This provides clarity and peace of mind for defenders looking to prioritize vulnerabilities more effectively in a challenging threat climate, rather than forcing them to speculate or rely on third-party research to answer questions that the supplier is best positioned to address,” said Caitlin Condon, vice president of security research at VulnCheck. 

“The easiest way to know whether this vulnerability, or any vulnerability, has been exploited would be for the vendor to explicitly disclose whether they’re aware of confirmed malicious activity in customer environments,” she said.

The maximum-severity score designated to CVE-2025-10035 is a revealing signal, Condon added. “It’s unusual for a vendor to assign a perfect 10 CVSS score unless they’ve validated vulnerability details and confirmed how an adversary would conduct a successful attack,” she said. 

Forta has been through this before. Its customers were previously targeted with a widely exploited zero-day vulnerability in the same file-transfer service two years ago. Fortra’s description of CVE-2025-10035 bears striking similarities to CVE-2023-0669, a defect exploited by Clop, resulting in attacks on more than 100 organizations, and at least five other ransomware groups.

Harris criticized Fortra for its reluctance to share crucial information.

“As an organization that signed CISA’s Secure By Design pledge that includes wording around transparency for in-the-wild exploitation, the situation seems rather disappointing,” he said. 

Enterprises, security professionals and defenders rely on accurate data to determine exposure and react accordingly, Harris added. 

“When transparency is missing, these same teams are left in the dark and left with inadequate information to make risk decisions,” he said. “Given the context of the solution being used, and the organizations that use this solution, we cannot understate the impact of additional dwell time for an attacker in some of these environments.”

The post Worries mount over max-severity GoAnywhere defect appeared first on CyberScoop.

Researchers warned that a maximum-severity vulnerability affecting GoAnywhere MFT bears striking similarities with a widely exploited defect in the same file-transfer service two years ago.

Fortra, the cybersecurity vendor behind the product, disclosed and released a patch for the vulnerability — CVE-2025-10035 — Thursday. The deserialization vulnerability “allows an actor with a validly forged license response signature to deserialize an arbitrary actor-controlled object, possibly leading to command injection,” the company said in a security advisory.

File transfer services are a valuable target for attackers because they store a lot of sensitive data. If cybercriminals exploit these services, they can quickly access information from many users at once, making these services especially attractive for large-scale attacks. 

Fortra didn’t provide any evidence of active exploitation and researchers from multiple security firms said they haven’t observed exploitation but expect that to change soon. “We believe that it’s just a matter of time and are monitoring the situation closely,” Ryan Dewhurst, head of proactive threat intelligence at watchTowr, said in an email.

The vulnerability, which has a CVSS rating of 10, is “virtually identical to the description for CVE-2023-0669,” a zero-day vulnerability exploited by Clop, resulting in attacks on more than 100 organizations, and at least five other ransomware groups, Caitlin Condon, vice president of security research at VulnCheck, said in a blog post. 

Clop, a highly prolific, financially motivated ransomware group, specializes in exploiting vulnerabilities in file-transfer services. The threat group achieved mass exploitation as it infiltrated MOVEit environments in 2023, ultimately exposing data from more than 2,300 organizations, making it the largest and most significant cyberattack that year.

“By design, file transfer services process and store sensitive files,” Dewhurst said. “These are a prime target for threat actors, especially ransomware groups, which can use the exposed files as blackmail.”

Stephen Fewer, senior principal researcher at Rapid7, noted that file-transfer services are often exposed to the internet with network credentials supporting data access, storage and flow — factors that create a high-value target for attackers. 

The new defect doesn’t require authentication, and deserialization vulnerabilities are typically more reliable than other bugs, including memory-corruption errors, Fewer said.

Researchers aren’t aware of publicly available proof-of-concept exploit code, yet it could exist privately. “As always, if the vulnerability turns out to have been exploited in the wild as a zero-day — which was unclear at time of disclosure — patching alone will not eradicate adversaries from compromised systems,” Condon said.

Fortra told CyberScoop it discovered the vulnerability during a security check Sept. 11. “We identified that GoAnywhere customers with an admin console accessible over the internet could be vulnerable to unauthorized third-party exposure,” Jessica Ryan, public relations manager at Fortra, said in an email. 

“We immediately developed a patch and offered customers mitigation guidance to help resolve the issue,” she added.

The managed file-transfer service is one of three GoAnywhere products used by more than 3,000 organizations, including Fortune 500 businesses, according to Fortra.

The vendor appears three times on the Cybersecurity and Infrastructure Security Agency’s known exploited vulnerabilities catalog, with all three defects added under a two-month period in 2023.

The post Researchers raise alarm over maximum-severity defect in GoAnywhere file-transfer service appeared first on CyberScoop.

Researchers and authorities are warning that Akira ransomware attacks involving exploits of a year-old vulnerability affecting SonicWall firewalls are on the rise. 

A burst of about 40 attacks linked to CVE-2024-40766 hit SonicWall firewalls between mid-July and early August. Researchers have since observed another wave of ransomware attacks linked to active exploits of the defect, which affects the secure sockets layer (SSL) VPN protocol in multiple versions of SonicWall firewalls, and configuration errors. 

Rapid7 has responded to a “double-digit number of attacks” related to the vulnerability and a series of misconfigurations in victim environments, the company said, expanding on a blog it published earlier this week.

The Australian Cyber Security Centre also issued an advisory Wednesday noting that it, too, is responding to a recent increase in active exploitation of the defect. “We are aware of the Akira ransomware targeting vulnerable Australian organisations through SonicWall SSL VPNs,” the agency said.

Rapid7’s incident response team told CyberScoop it has spotted a steady increase in attacks since July, sometimes multiple incidents per week among its customers. The narrow scope of Rapid7’s visibility suggests impact could be much wider. 

SonicWall, which initially disclosed the vulnerability in August 2024, did not respond to a request for comment. Previously patched but improperly configured devices are showing up in many compromised environments. 

“In the vast majority of cases our team is working, the SonicWall firewalls have been upgraded to a version that patches CVE-2024-40766,” Rapid7’s incident response team said in an email. “The remediation step of changing local passwords was not completed, and attackers were therefore able to gain unauthorized access to the devices.”

SonicWall last month said many of the attacks in late July involved customers that migrated from Gen 6 to Gen 7 firewalls without resetting passwords. Customers have since been impacted by multiple configuration errors, according to Rapid7.

Researchers have identified attackers abusing default lightweight directory access protocol (LDAP) group configurations, which can overprovision access to SonicWall’s SSL VPN services. Attackers have also accessed the virtual office portal on SonicWall devices, likely in a bid to find users with compromised credentials or accounts lacking multifactor authentication, according to Rapid7.

The root cause of attacks targeting SonicWall devices has shifted since researchers suggested a zero-day vulnerability might have been involved in the first series of attacks in July. SonicWall ruled that out in early August, as more attacks were discovered, and pinned the attacks on CVE-2024-40766. 

SonicWall customers are no stranger to actively exploited vulnerabilities. The vendor has appeared 14 times on CISA’s known exploited vulnerabilities catalog since late 2021. Nine of those defects are known to be used in ransomware campaigns, according to CISA.

Rapid7 attributes all of the recent attacks involving SonicWall firewalls to Akira ransomware. 

Akira affiliates typically steal data and encrypt systems before they attempt to extort victims. Akira ransomware impacted more than 250 organizations from March 2023 to January 2024, claiming about $42 million in extortion payments, CISA said in an advisory last year.

The post SonicWall firewalls targeted by fresh Akira ransomware surge appeared first on CyberScoop.

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.

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.

Microsoft today released updates to fix at least 137 security vulnerabilities in its Windows operating systems and supported software. None of the weaknesses addressed this month are known to be actively exploited, but 14 of the flaws earned Microsoft’s most-dire “critical” rating, meaning they could be exploited to seize control over vulnerable Windows PCs with little or no help from users.

While not listed as critical, CVE-2025-49719 is a publicly disclosed information disclosure vulnerability, with all versions as far back as SQL Server 2016 receiving patches. Microsoft rates CVE-2025-49719 as less likely to be exploited, but the availability of proof-of-concept code for this flaw means its patch should probably be a priority for affected enterprises.

Mike Walters, co-founder of Action1, said CVE-2025-49719 can be exploited without authentication, and that many third-party applications depend on SQL server and the affected drivers — potentially introducing a supply-chain risk that extends beyond direct SQL Server users.

“The potential exposure of sensitive information makes this a high-priority concern for organizations handling valuable or regulated data,” Walters said. “The comprehensive nature of the affected versions, spanning multiple SQL Server releases from 2016 through 2022, indicates a fundamental issue in how SQL Server handles memory management and input validation.”

Adam Barnett at Rapid7 notes that today is the end of the road for SQL Server 2012, meaning there will be no future security patches even for critical vulnerabilities, even if you’re willing to pay Microsoft for the privilege.

Barnett also called attention to CVE-2025-47981, a vulnerability with a CVSS score of 9.8 (10 being the worst), a remote code execution bug in the way Windows servers and clients negotiate to discover mutually supported authentication mechanisms. This pre-authentication vulnerability affects any Windows client machine running Windows 10 1607 or above, and all current versions of Windows Server. Microsoft considers it more likely that attackers will exploit this flaw.

Microsoft also patched at least four critical, remote code execution flaws in Office (CVE-2025-49695, CVE-2025-49696, CVE-2025-49697, CVE-2025-49702). The first two are both rated by Microsoft as having a higher likelihood of exploitation, do not require user interaction, and can be triggered through the Preview Pane.

Two more high severity bugs include CVE-2025-49740 (CVSS 8.8) and CVE-2025-47178 (CVSS 8.0); the former is a weakness that could allow malicious files to bypass screening by Microsoft Defender SmartScreen, a built-in feature of Windows that tries to block untrusted downloads and malicious sites.

CVE-2025-47178 involves a remote code execution flaw in Microsoft Configuration Manager, an enterprise tool for managing, deploying, and securing computers, servers, and devices across a network. Ben Hopkins at Immersive said this bug requires very low privileges to exploit, and that it is possible for a user or attacker with a read-only access role to exploit it.

“Exploiting this vulnerability allows an attacker to execute arbitrary SQL queries as the privileged SMS service account in Microsoft Configuration Manager,” Hopkins said. “This access can be used to manipulate deployments, push malicious software or scripts to all managed devices, alter configurations, steal sensitive data, and potentially escalate to full operating system code execution across the enterprise, giving the attacker broad control over the entire IT environment.”

Separately, Adobe has released security updates for a broad range of software, including After Effects, Adobe Audition, Illustrator, FrameMaker, and ColdFusion.

The SANS Internet Storm Center has a breakdown of each individual patch, indexed by severity. If you’re responsible for administering a number of Windows systems, it may be worth keeping an eye on AskWoody for the lowdown on any potentially wonky updates (considering the large number of vulnerabilities and Windows components addressed this month).

If you’re a Windows home user, please consider backing up your data and/or drive before installing any patches, and drop a note in the comments if you encounter any problems with these updates.

Microsoft today released security updates to fix at least 67 vulnerabilities in its Windows operating systems and software. Redmond warns that one of the flaws is already under active attack, and that software blueprints showing how to exploit a pervasive Windows bug patched this month are now public.

The sole zero-day flaw this month is CVE-2025-33053, a remote code execution flaw in the Windows implementation of WebDAV — an HTTP extension that lets users remotely manage files and directories on a server. While WebDAV isn’t enabled by default in Windows, its presence in legacy or specialized systems still makes it a relevant target, said Seth Hoyt, senior security engineer at Automox.

Adam Barnett, lead software engineer at Rapid7, said Microsoft’s advisory for CVE-2025-33053 does not mention that the Windows implementation of WebDAV is listed as deprecated since November 2023, which in practical terms means that the WebClient service no longer starts by default.

“The advisory also has attack complexity as low, which means that exploitation does not require preparation of the target environment in any way that is beyond the attacker’s control,” Barnett said. “Exploitation relies on the user clicking a malicious link. It’s not clear how an asset would be immediately vulnerable if the service isn’t running, but all versions of Windows receive a patch, including those released since the deprecation of WebClient, like Server 2025 and Windows 11 24H2.”

Microsoft warns that an “elevation of privilege” vulnerability in the Windows Server Message Block (SMB) client (CVE-2025-33073) is likely to be exploited, given that proof-of-concept code for this bug is now public. CVE-2025-33073 has a CVSS risk score of 8.8 (out of 10), and exploitation of the flaw leads to the attacker gaining “SYSTEM” level control over a vulnerable PC.

“What makes this especially dangerous is that no further user interaction is required after the initial connection—something attackers can often trigger without the user realizing it,” said Alex Vovk, co-founder and CEO of Action1. “Given the high privilege level and ease of exploitation, this flaw poses a significant risk to Windows environments. The scope of affected systems is extensive, as SMB is a core Windows protocol used for file and printer sharing and inter-process communication.”

Beyond these highlights, 10 of the vulnerabilities fixed this month were rated “critical” by Microsoft, including eight remote code execution flaws.

Notably absent from this month’s patch batch is a fix for a newly discovered weakness in Windows Server 2025 that allows attackers to act with the privileges of any user in Active Directory. The bug, dubbed “BadSuccessor,” was publicly disclosed by researchers at Akamai on May 21, and several public proof-of-concepts are now available. Tenable’s Satnam Narang said organizations that have at least one Windows Server 2025 domain controller should review permissions for principals and limit those permissions as much as possible.

Adobe has released updates for Acrobat Reader and six other products addressing at least 259 vulnerabilities, most of them in an update for Experience Manager. Mozilla Firefox and Google Chrome both recently released security updates that require a restart of the browser to take effect. The latest Chrome update fixes two zero-day exploits in the browser (CVE-2025-5419 and CVE-2025-4664).

For a detailed breakdown on the individual security updates released by Microsoft today, check out the Patch Tuesday roundup from the SANS Internet Storm Center. Action 1 has a breakdown of patches from Microsoft and a raft of other software vendors releasing fixes this month. As always, please back up your system and/or data before patching, and feel free to drop a note in the comments if you run into any problems applying these updates.

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.

Microsoft today issued more than 50 security updates for its various Windows operating systems, including fixes for a whopping six zero-day vulnerabilities that are already seeing active exploitation.

Two of the zero-day flaws include CVE-2025-24991 and CVE-2025-24993, both vulnerabilities in NTFS, the default file system for Windows and Windows Server. Both require the attacker to trick a target into mounting a malicious virtual hard disk. CVE-2025-24993 would lead to the possibility of local code execution, while CVE-2025-24991 could cause NTFS to disclose portions of memory.

Microsoft credits researchers at ESET with reporting the zero-day bug labeled CVE-2025-24983, an elevation of privilege vulnerability in older versions of Windows. ESET said the exploit was deployed via the PipeMagic backdoor, capable of exfiltrating data and enabling remote access to the machine.

ESET’s Filip Jurčacko said the exploit in the wild targets only older versions of Windows OS: Windows 8.1 and Server 2012 R2. Although still used by millions, security support for these products ended more than a year ago, and mainstream support ended years ago. However, ESET notes the vulnerability itself also is present in newer Windows OS versions, including Windows 10 build 1809 and the still-supported Windows Server 2016.

Rapid7’s lead software engineer Adam Barnett said Windows 11 and Server 2019 onwards are not listed as receiving patches, so are presumably not vulnerable.

“It’s not clear why newer Windows products dodged this particular bullet,” Barnett wrote. “The Windows 32 subsystem is still presumably alive and well, since there is no apparent mention of its demise on the Windows client OS deprecated features list.”

The zero-day flaw CVE-2025-24984 is another NTFS weakness that can be exploited by inserting a malicious USB drive into a Windows computer. Barnett said Microsoft’s advisory for this bug doesn’t quite join the dots, but successful exploitation appears to mean that portions of heap memory could be improperly dumped into a log file, which could then be combed through by an attacker hungry for privileged information.

“A relatively low CVSSv3 base score of 4.6 reflects the practical difficulties of real-world exploitation, but a motivated attacker can sometimes achieve extraordinary results starting from the smallest of toeholds, and Microsoft does rate this vulnerability as important on its own proprietary severity ranking scale,” Barnett said.

Another zero-day fixed this month — CVE-2025-24985 — could allow attackers to install malicious code. As with the NTFS bugs, this one requires that the user mount a malicious virtual hard drive.

The final zero-day this month is CVE-2025-26633, a weakness in the Microsoft Management Console, a component of Windows that gives system administrators a way to configure and monitor the system. Exploiting this flaw requires the target to open a malicious file.

This month’s bundle of patch love from Redmond also addresses six other vulnerabilities Microsoft has rated “critical,” meaning that malware or malcontents could exploit them to seize control over vulnerable PCs with no help from users.

Barnett observed that this is now the sixth consecutive month where Microsoft has published zero-day vulnerabilities on Patch Tuesday without evaluating any of them as critical severity at time of publication.

The SANS Internet Storm Center has a useful list of all the Microsoft patches released today, indexed by severity. Windows enterprise administrators would do well to keep an eye on askwoody.com, which often has the scoop on any patches causing problems. Please consider backing up your data before updating, and leave a comment below if you experience any issues applying this month’s updates.