CISA has added CVE-2026-111357 and CVE-2026-118527 to its KEV catalog after the Ivanti VPN flaws were chained in zero-day attacks.

The post Ivanti Patches Two More Zero-Days Exploited in Connect Secure Attack Chain appeared first on SecurityWeek.

Volt Typhoon, a China-government backed hacking group that has infiltrated America’s critical infrastructure networks for years, has consistently built and dismantled ephemeral malicious infrastructure to burrow into hundreds of sensitive systems undetected, Lumen Technologies’ Black Lotus Labs said in a Wednesday report.

The covert access operation that researchers call “Silent Train” isn’t a standalone network, but rather a series of compromised small office home office (SOHO) routers, internet of things (IoT) devices and enterprise infrastructure that Volt Typhoon has rapidly rotated through since late 2023. 

The Chinese threat group has used this chain of short-lived compromised infrastructure to exploit additional vulnerabilities, including zero-days, in network edge devices and gain deeper, persistent access into victim networks, researchers said. 

“Individual chains are assembled and dismantled every day, with infrastructure continually refreshed,” Michael Horka, principal information security engineer at Black Lotus Labs, told CyberScoop. “Volt Typhoon demonstrated a repeatable capability to rebuild a new chain with different infrastructure in less than two minutes, making the number of nodes at any one moment effectively close to zero.”

Black Lotus Labs has notified hundreds of victims since it first identified Silent Train activity, including telecom providers, government entities, defense contractors, communication services, universities and IT firms. Other victims spanning critical infrastructure include organizations in the water, energy, transportation, maritime, rail, aviation and emergency services sectors.

“The ephemeral nature of the framework means our observations should not be interpreted as a complete census of Volt Typhoon activity,” said Horka, who also was the lead researcher on the report.

The nation-state group’s investment in operational security and preserving access is remarkable, according to Black Lotus Labs.

“We observed infrastructure assembled in under two minutes, sessions averaging roughly four hours, extensive cleanup, compartmentalization and continued development of new access vectors,” Horka said. “That is considerable effort devoted not even to get into their end targets, but purely to making important operations difficult to discover and trace.”

Volt Typhoon relied more heavily on Silent Train after the FBI and Justice Department disrupted the KV Botnet in early 2024, researchers said. Earlier this year, U.S. and global authorities warned about a widespread shift in Chinese hacking groups’ use of covert networks riding on compromised common devices.

The reach of those efforts is extensive and ongoing. Volt Typhoon has exploited and abused more than 27 device classes in Silent Train operations, including edge devices, enterprise management tools, identity and access management systems, networking infrastructure and other technologies. 

“The diversity matters, but the discipline matters even more,” Horka said. “Specific device types were consistently reserved for particular positions in the chain. It operated less like a collection of randomly compromised devices and more like an organized inventory of capabilities.”

The threat group has successfully compromised devices and technologies from Fortinet, Cisco, ManageEngine, Ivanti, F5, Check Point, Palo Alto Networks, ServiceNow, TP-Link, Netgear and ArcGIS, researchers said. Black Lotus Labs also observed confirmed zero-day campaigns targeting Versa Director, N-Able N-Central, Cisco Catalyst SD-WAN and VeloCloud Orchestrator. 

“The exploitation patterns, victimology, and geographic targeting observed throughout our investigation point to a sustained focus on communications, defense, government, and critical infrastructure environments of enduring strategic value,” Black Lotus Labs researchers wrote in the report. “Through repeated targeting of centralized management platforms and control-plane technologies, Silent Train shows how Volt Typhoon systematically pursues and preserves access to some of the most consequential networks in the United States.”

Silent Train’s ephemerality and operational discipline means it can’t be measured in size. These attributes also make it “fundamentally difficult to disrupt because there isn’t one network to take down,” Horka said. 

“What exists today will be completely different tomorrow,” he added. “You can try to remove individual pieces, but removing the actor’s ability to continuously rebuild them is a much harder problem to solve.”

The post Researchers uncover Volt Typhoon’s covert, ephemeral network appeared first on CyberScoop.

Suspected Chinese hackers with a proven knack for exploiting zero-days in security products are at it again, targeting BeyondTrust customers in attacks that researchers have traced back to late August. 

Mandiant researchers said a likely Chinese government-backed espionage group it previously tracked as UNC5221, and now calls Armory Castle, exploited the critical defect — CVE-2026-102764 — then showcased multiple tactics to escalate privileges, hop around the compromised network and evade detection. 

The same threat group has repeatedly exploited a series of defects in Ivanti products since 2023, a Citrix NetScaler zero-day widely known as CitrixBleed, and last year’s Brickstorm campaign that had an average dwell time of 400 days — all resulting in sweeping attack sprees.

“We are aware of only a small number of impacted organizations at this time, but given the stealth of the activity, and the use of a zero-day, it is possible that additional organizations were also compromised prior to the disclosure,” Kelli Vanderlee, senior analyst at Google Threat Intelligence Group, said in an email.

Mandiant warned organizations to “prepare for potential widespread exploitation,” adding that Armory Castle and other threat groups previously conducted broad, opportunistic exploitation following public vulnerability disclosures.

Mandiant and GTIG released their analysis of Armory Castle and its latest campaign as BeyondTrust publicly disclosed the vulnerability in its Remote Support product Thursday. The company’s security said it released a patch for the exploited defect for self-hosted customers Oct. 8 and automatically applied the update to cloud-based versions of the product that same day.

BeyondTrust, which conducted its own investigation and coordinated with Mandiant on an investigation involving a self-hosted customer that was compromised, noted Armory Castle’s prowess.

“This threat actor rotates its infrastructure and tooling for every victim, so attribution here rests on behavior. The indicators from one intrusion rarely survive to the next,” the company’s security team wrote in a blog post. “The threat actor has historically demonstrated a high degree of operational security awareness, professional practices, and tradecraft.”

A BeyondTrust spokesperson declined to answer questions about how many customers are already compromised or why it didn’t publicly disclose the actively exploited zero-day sooner, and instead referred back to its security advisory. 

The company said the first known instance of zero-day exploitation occurred Aug. 29, which it detected and contained Sept. 28. 

BeyondTrust also said it detected the malicious activity after zero-days were confirmed to be exploited in another security vendor’s product Sept. 27. That timing matches a round of zero-days Citrix NetScaler disclosed, following nearly two days of rampant worry and unconfirmed rumors. 

BeyondTrust did not say if there is any link or overlap between the attacks targeting Citrix NetScaler, which went undetected for more than three weeks, and its remote access product. 

GTIG researchers said there isn’t enough evidence to assess an overall targeting trend, but encouraged all potentially vulnerable organizations to apply the patch and hunt for pre-disclosure activity. 

The threat group’s previous targets include business-process outsourcers, government, legal services, technology companies and software-as-a-service providers.

“Armory Castle remains one of the most prominent China-nexus threat actors due to its persistent targeting of various edge device technologies, use of zero-day vulnerabilities for widespread exploitation across multiple industries and regions, and its continuously expanding and evolving arsenal of tools,” said Dan Perez, technical lead at GTIG.

“This is a well-established pattern for Armory Castle,” Vanderlee said. “Targeting edge devices, which typically do not support endpoint detection and response (EDR), allows the threat actor to minimize opportunities for detection and maintain stealthy, persistent access to targeted networks.”

The post Prolific Chinese espionage group exploits BeyondTrust zero-day appeared first on CyberScoop.

Critical-severity flaws could lead to authentication bypass, code execution, and sensitive authentication information leaks.

The post Citrix, Fortinet, Ivanti Patch 29 Vulnerabilities Across Their Products appeared first on SecurityWeek.

CVE-2026-104935 affects Ivanti Connect Secure and it can be exploited for unauthenticated remote code execution with elevated privileges. 

The post Ivanti Zero-Day Chain Gave Attackers Root Access to Fully Patched VPN appeared first on SecurityWeek.

Ivanti customers are in familiar territory, responding to yet another actively exploited zero-day affecting one of the vendor’s most commonly targeted security products. 

Volexity researchers, which discovered in-the-wild exploitation earlier this month, said attackers actually exploited three zero-days in a chain that allowed them to bypass authentication, execute code remotely and escalate privileges. 

Ivanti disclosed and issued a patch for the authentication bypass and remote-code execution components of the exploit chain as a single vulnerability in Ivanti Connect Secure. The company said it initially discovered a portion of the high-severity vulnerability — CVE-2026-104935 — during internal security checks in June.

A threat actor, which Volexity tracks as UTA0576, exploited the defects before Ivanti addressed them and issued a patch.

“Because the issue was discovered internally, was not being actively exploited, and did not meet the threshold for an out-of-band release, a fix was scheduled for inclusion in our normal product release cycle,” an Ivanti spokesperson wrote in response to questions.

“Successful exploitation requires chaining multiple vulnerabilities and Ivanti has fully addressed the unauthenticated remote code execution component of that chain, eliminating the primary exploitation path,” the spokesperson added. “We are also developing additional updates to address the remaining vulnerability and further strengthen product security.”

The full scope of compromise remains under investigation. The company, in a security advisory, said a “limited number of customers” were already compromised prior to disclosure. 

The Cybersecurity and Infrastructure Security Agency added the defect to its known exploited vulnerabilities catalog Tuesday.

Sean Koessel, vice president of professional services at Volexity, said the earliest confirmed instance of exploitation occurred Oct. 1. Yet, “it wouldn’t surprise us if there was activity toward the end of September,” he added.

Volexity researchers observed a series of post-exploitation activities during an investigation involving a customer’s compromised Ivanti Connect Secure VPN appliance earlier this month. “UTA0576 repeatedly exploited these vulnerabilities to compromise the ICS VPN appliance and run commands on it,” the company wrote in a blog post. 

The threat actor extracted credentials stored on the device, dumped and stole Active Directory metadata, and deployed multiple custom and malicious tools capable of facilitating follow-on attacks, credential testing and hunting for administrator passwords, recovery keys and other passwords.

“Based on Volexity’s observations, UTA0576 primarily focused on credential theft, data exfiltration, log tampering, and network reconnaissance,” the company added.

Ivanti encouraged potentially vulnerable customers to act immediately by upgrading to the latest version of software, running the company’s Integrity Checker Tool regularly, and reviewing indicators of compromise published by Volexity.

CISA also urged Ivanti customers to patch the vulnerability quickly, as it dissuaded customers from relying on the company’s Integrity Checker Tool.

“Organizations seeking to determine whether they were compromised will need to conduct network and memory forensics to identify evidence of exploitation,” the agency said in an alert Tuesday. “Ivanti’s Integrity Checker Tool may not detect evidence of exploitation of CVE-2026-104935 because threat actor commands execute in memory.”

Ivanti products, including Ivanti Connect Secure, are a frequent target for attackers of various motivations in the network edge space. 

CISA has flagged 36 Ivanti defects on its known exploited vulnerabilities catalog since late 2021. At least 6 defects across Ivanti products have been exploited since late January.

“Edge devices are a valuable initial foothold and often enable attackers to pivot further into targeted networks,” Koessel said. “It would be fair to expect widespread exploitation, this is a common theme with most vulnerabilities in edge devices.”

Other researchers also expect exploitation to pick up rapidly. 

“Given the history of attacker attention and focus Ivanti Connect Secure has previously drawn — and the trivial nature of the authentication bypass — widespread, indiscriminate exploitation is inevitable as attackers begin reviewing patches and public information,” said Yordan Ganchev, principal threat intelligence specialist at watchTowr.

“The race condition required for code execution offers little resistance, as an unauthenticated attacker can repeatedly attempt exploitation until it succeeds,” he added.

The post Ivanti misses opportunity to fix vulnerability before attackers got to work and made it a zero-day appeared first on CyberScoop.

Microsoft Corp. today released software updates to plug at least 570 security holes in its Windows operating systems and other software, almost triple the number of vulnerabilities the software giant fixed in its record-smashing Patch Tuesday release last month. Microsoft attributed the burgeoning patch counts to vulnerability discoveries aided by artificial intelligence.

Nearly 60 of the bugs quashed in July’s Patch Tuesday earned a “critical” severity rating, meaning miscreants or malware could use them to seize remote control over a Windows device with little or no help from the user. Microsoft also addressed three zero-day flaws, including two that are already being exploited in the wild.

Two of the zero-day weaknesses allow an attacker to elevate their user rights on a Windows system, as do approximately 250 other elevation of privilege flaws fixed this month; they include CVE-2026-56155 — an Active Directory Federation Services bug — and CVE-2026-56164, a Microsoft Sharepoint vulnerability.

CVE-2026-50661 is a security feature bypass in Windows BitLocker that could allow attackers to gain access to encrypted data if they have physical access to the device. Microsoft said this bug has been detailed publicly, but that it is not aware of any active exploitation.

In a blog post on July 9, Microsoft Executive Vice President Pavan Davuluri wrote that Windows users will notice “a higher volume of security updates included in each security release” as a result of AI aiding in the discovery of vulnerabilities.

“The pace of vulnerability discovery is changing with advances in AI making it possible to find more issues, faster, across more code, with new mechanisms that can accelerate both discovery and analysis,” Davuluri wrote.

Jack Bicer, director of vulnerability research at Action1, called attention to CVE-2026-48561, a remote code execution flaw in Microsoft Copilot (with a 9.6 CVSS threat score) that allows an unauthorized attacker to execute code over the network. Microsoft says an attacker could exploit this bug by hosting a malicious website that causes Microsoft Edge for Android to automatically send crafted prompts to Copilot when a user visits the site.

As AI advances the state of vulnerability discovery and remediation, it is also making it easier for attackers to quickly devise working exploits for known software flaws. Microsoft has long labeled security bugs using its “exploitability index,” which is Redmond’s best guess as to how likely it is that attackers will be able to figure out a reliable way to exploit a given vulnerability.

But Satnam Narang, senior staff research engineer at Tenable, argues that Microsoft’s exploitability index needs to do a better job of shifting with the machine speed of discovery. For example, Microsoft originally gave this month’s SharePoint zero-day an exploitability rating of “less likely,” although the flaw was added to CISA’s Known Exploited Vulnerabilities list on July 1.

“Anthropic’s Red Team’s own findings for known vulnerabilities (n-days) revealed how fragile this system has become, with its Mythos Preview model being able to produce proof-of-concept exploits for 13 of 14 vulnerabilities that were rated ‘Exploitation Less Likely’ or ‘Exploitation Unlikely,'” Narang said. “What this means is that our way of looking at Patch Tuesday has changed, because the exploitability index is centered around humans, not AI tools, and as these tools continue to improve, defense needs to improve alongside it.”

Chris Goettl at Ivanti observed that the record patch numbers from Microsoft come as a number of other major software makers are increasing their patch cadence, including Adobe which announced today it is moving to twice-monthly security bulletins published on the 2nd and 4th Tuesday of each month (Adobe also cited AI for accelerating their patch cycles). Cisco, Mozilla and Oracle also are shipping updates more frequently, while Google’s patch batches in June 2026 totaled more than 900 security fixes, Goettl noted.

Backing up your Windows system and/or data is always a good idea before applying operating system updates. Given the volume of patches addressed this month it may be wise for end users to wait a few days before applying these fixes. It’s not uncommon for security patches to introduce system stability issues, and those chances probably increase quite a bit with the gigantic patch count released today.

Further reading:

Action1’s Patch Tuesday blog

Automox’s rundown

Artificial intelligence platforms may be just as susceptible to social engineering as human beings, but they are proving remarkably good at finding security vulnerabilities in human-made computer code. That reality is on full display this month with some of the more widely-used software makers — including Apple, Google, Microsoft, Mozilla and Oracle — fixing near record volumes of security bugs, and/or quickening the tempo of their patch releases.

As it does on the second Tuesday of every month, Microsoft today released software updates to address at least 118 security vulnerabilities in its various Windows operating systems and other products. Remarkably, this is the first Patch Tuesday in nearly two years that Microsoft is not shipping any fixes to deal with emergency zero-day flaws that are already being exploited. Nor have any of the flaws fixed today been previously disclosed (potentially giving attackers a heads up in how to exploit the weakness).

Sixteen of the vulnerabilities earned Microsoft’s most-dire “critical” label, meaning malware or miscreants could abuse these bugs to seize remote control over a vulnerable Windows device with little or no help from the user. Rapid7 has done much of the heavy lifting in identifying some of the more concerning critical weaknesses this month, including:

• CVE-2026-41089: A critical stack-based buffer overflow in Windows Netlogon that offers an attacker SYSTEM privileges on the domain controller. No privileges or user interaction are required, and attack complexity is low. Patches are available for all versions of Windows Server from 2012 onwards.
• CVE-2026-41096: A critical RCE in the Windows DNS client implementation worthy of attention despite Microsoft assessing exploitation as less likely.
• CVE-2026-41103: A critical elevation of privilege vulnerability that allows an unauthorized attacker to impersonate an existing user by presenting forged credentials, thus bypassing Entra ID. Microsoft expects that exploitation is more likely.

May’s Patch Tuesday is a welcome respite from April, which saw Microsoft fix a near-record 167 security flaws. Microsoft was among a few dozen tech giants given access to a “Project Glasswing,” a much-hyped AI capability developed by Anthropic that appears quite effective at unearthing security vulnerabilities in code.

Apple, another early participant in Project Glasswing, typically fixes an average of 20 vulnerabilities each time it ships a security update for iOS devices, said Chris Goettl, vice president of product management at Ivanti. On May 11, Apple shipped updates to address at least 52 vulnerabilities and backported the changes all the way to iPhone 6s and iOS 15.

Last month, Mozilla released Firefox 150, which resolved a whopping 271 vulnerabilities that were reportedly discovered during the Glasswing evaluation.

“Since Firefox 150.0.0 released, they have been on a more aggressive weekly cadence for security updates including the release of Firefox 150.0.3 on May Patch Tuesday resolving between three to five CVEs in each release,” Goettl said.

The software giant Oracle likewise recently increased its patch pace in response to their work with Glasswing. In its most recent quarterly patch update, Oracle addressed at least 450 flaws, including more than 300 fixes for remotely exploitable, unauthenticated flaws. But at the end of April, Oracle announced it was switching to a monthly update cycle for critical security issues.

On May 8, Google started rolling out updates to its Chrome browser that fixed an astonishing 127 security flaws (up from just 30 the previous month). Chrome automagically downloads available security updates, but installing them requires fully restarting the browser.

If you encounter any weirdness applying the updates from Microsoft or any other vendor mentioned here, feel free to sound off in the comments below. Meantime, if you haven’t backed up your data and/or drive lately, doing that before updating is generally sound advice. For a more granular look at the Microsoft updates released today, checkout this inventory by the SANS Internet Storm Center.

Microsoft today released updates to fix more than 50 security holes in its Windows operating systems and other software, including patches for a whopping six “zero-day” vulnerabilities that attackers are already exploiting in the wild.

Zero-day #1 this month is CVE-2026-21510, a security feature bypass vulnerability in Windows Shell wherein a single click on a malicious link can quietly bypass Windows protections and run attacker-controlled content without warning or consent dialogs. CVE-2026-21510 affects all currently supported versions of Windows.

The zero-day flaw CVE-2026-21513 is a security bypass bug targeting MSHTML, the proprietary engine of the default Web browser in Windows. CVE-2026-21514 is a related security feature bypass in Microsoft Word.

The zero-day CVE-2026-21533 allows local attackers to elevate their user privileges to “SYSTEM” level access in Windows Remote Desktop Services. CVE-2026-21519 is a zero-day elevation of privilege flaw in the Desktop Window Manager (DWM), a key component of Windows that organizes windows on a user’s screen. Microsoft fixed a different zero-day in DWM just last month.

The sixth zero-day is CVE-2026-21525, a potentially disruptive denial-of-service vulnerability in the Windows Remote Access Connection Manager, the service responsible for maintaining VPN connections to corporate networks.

Chris Goettl at Ivanti reminds us Microsoft has issued several out-of-band security updates since January’s Patch Tuesday. On January 17, Microsoft pushed a fix that resolved a credential prompt failure when attempting remote desktop or remote application connections. On January 26, Microsoft patched a zero-day security feature bypass vulnerability (CVE-2026-21509) in Microsoft Office.

Kev Breen at Immersive notes that this month’s Patch Tuesday includes several fixes for remote code execution vulnerabilities affecting GitHub Copilot and multiple integrated development environments (IDEs), including VS Code, Visual Studio, and JetBrains products. The relevant CVEs are CVE-2026-21516, CVE-2026-21523, and CVE-2026-21256.

Breen said the AI vulnerabilities Microsoft patched this month stem from a command injection flaw that can be triggered through prompt injection, or tricking the AI agent into doing something it shouldn’t — like executing malicious code or commands.

“Developers are high-value targets for threat actors, as they often have access to sensitive data such as API keys and secrets that function as keys to critical infrastructure, including privileged AWS or Azure API keys,” Breen said. “When organizations enable developers and automation pipelines to use LLMs and agentic AI, a malicious prompt can have significant impact. This does not mean organizations should stop using AI. It does mean developers should understand the risks, teams should clearly identify which systems and workflows have access to AI agents, and least-privilege principles should be applied to limit the blast radius if developer secrets are compromised.”

The SANS Internet Storm Center has a clickable breakdown of each individual fix this month 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. Please don’t neglect to back up your data if it has been a while since you’ve done that, and feel free to sound off in the comments if you experience problems installing any of these fixes.

Microsoft today issued patches to plug at least 113 security holes in its various Windows operating systems and supported software. Eight of the vulnerabilities earned Microsoft’s most-dire “critical” rating, and the company warns that attackers are already exploiting one of the bugs fixed today.

January’s Microsoft zero-day flaw — CVE-2026-20805 — is brought to us by a flaw in the Desktop Window Manager (DWM), a key component of Windows that organizes windows on a user’s screen. Kev Breen, senior director of cyber threat research at Immersive, said despite awarding CVE-2026-20805 a middling CVSS score of 5.5, Microsoft has confirmed its active exploitation in the wild, indicating that threat actors are already leveraging this flaw against organizations.

Breen said vulnerabilities of this kind are commonly used to undermine Address Space Layout Randomization (ASLR), a core operating system security control designed to protect against buffer overflows and other memory-manipulation exploits.

“By revealing where code resides in memory, this vulnerability can be chained with a separate code execution flaw, transforming a complex and unreliable exploit into a practical and repeatable attack,” Breen said. “Microsoft has not disclosed which additional components may be involved in such an exploit chain, significantly limiting defenders’ ability to proactively threat hunt for related activity. As a result, rapid patching currently remains the only effective mitigation.”

Chris Goettl, vice president of product management at Ivanti, observed that CVE-2026-20805 affects all currently supported and extended security update supported versions of the Windows OS. Goettl said it would be a mistake to dismiss the severity of this flaw based on its “Important” rating and relatively low CVSS score.

“A risk-based prioritization methodology warrants treating this vulnerability as a higher severity than the vendor rating or CVSS score assigned,” he said.

Among the critical flaws patched this month are two Microsoft Office remote code execution bugs (CVE-2026-20952 and CVE-2026-20953) that can be triggered just by viewing a booby-trapped message in the Preview Pane.

Our October 2025 Patch Tuesday “End of 10” roundup noted that Microsoft had removed a modem driver from all versions after it was discovered that hackers were abusing a vulnerability in it to hack into systems. Adam Barnett at Rapid7 said Microsoft today removed another couple of modem drivers from Windows for a broadly similar reason: Microsoft is aware of functional exploit code for an elevation of privilege vulnerability in a very similar modem driver, tracked as CVE-2023-31096.

“That’s not a typo; this vulnerability was originally published via MITRE over two years ago, along with a credible public writeup by the original researcher,” Barnett said. “Today’s Windows patches remove agrsm64.sys and agrsm.sys. All three modem drivers were originally developed by the same now-defunct third party, and have been included in Windows for decades. These driver removals will pass unnoticed for most people, but you might find active modems still in a few contexts, including some industrial control systems.”

According to Barnett, two questions remain: How many more legacy modem drivers are still present on a fully-patched Windows asset; and how many more elevation-to-SYSTEM vulnerabilities will emerge from them before Microsoft cuts off attackers who have been enjoying “living off the land[line] by exploiting an entire class of dusty old device drivers?”

“Although Microsoft doesn’t claim evidence of exploitation for CVE-2023-31096, the relevant 2023 write-up and the 2025 removal of the other Agere modem driver have provided two strong signals for anyone looking for Windows exploits in the meantime,” Barnett said. “In case you were wondering, there is no need to have a modem connected; the mere presence of the driver is enough to render an asset vulnerable.”

Immersive, Ivanti and Rapid7 all called attention to CVE-2026-21265, which is a critical Security Feature Bypass vulnerability affecting Windows Secure Boot. This security feature is designed to protect against threats like rootkits and bootkits, and it relies on a set of certificates that are set to expire in June 2026 and October 2026. Once these 2011 certificates expire, Windows devices that do not have the new 2023 certificates can no longer receive Secure Boot security fixes.

Barnett cautioned that when updating the bootloader and BIOS, it is essential to prepare fully ahead of time for the specific OS and BIOS combination you’re working with, since incorrect remediation steps can lead to an unbootable system.

“Fifteen years is a very long time indeed in information security, but the clock is running out on the Microsoft root certificates which have been signing essentially everything in the Secure Boot ecosystem since the days of Stuxnet,” Barnett said. “Microsoft issued replacement certificates back in 2023, alongside CVE-2023-24932 which covered relevant Windows patches as well as subsequent steps to remediate the Secure Boot bypass exploited by the BlackLotus bootkit.”

Goettl noted that Mozilla has released updates for Firefox and Firefox ESR resolving a total of 34 vulnerabilities, two of which are suspected to be exploited (CVE-2026-0891 and CVE-2026-0892). Both are resolved in Firefox 147 (MFSA2026-01) and CVE-2026-0891 is resolved in Firefox ESR 140.7 (MFSA2026-03).

“Expect Google Chrome and Microsoft Edge updates this week in addition to a high severity vulnerability in Chrome WebView that was resolved in the January 6 Chrome update (CVE-2026-0628),” Goettl said.

As ever, the SANS Internet Storm Center has a per-patch breakdown by severity and urgency. Windows admins should keep an eye on askwoody.com for any news about patches that don’t quite play nice with everything. If you experience any issues related installing January’s patches, please drop a line in the comments below.