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A newly disclosed critical flaw in the Linux kernel allows code inside a virtual machine to read memory on the host computer it runs on. A researcher demonstrated the leak against Vercel's live cloud sandboxes, and Vercel confirmed it. The flaw, now tracked as CVE-2026-99999 and nicknamed PwnEscape , is in the Linux kernel's networking code, not in any one cloud's setup, so it reaches the shared layer that cloud providers use to keep customers' workloads apart. It was found in a Vercel security challenge and reported privately before any public release, and there is no sign it has been used in a real attack. What the Researcher Showed Paulos Yibelo of the security firm pwn.ai found that specially made network packets sent from inside a virtual machine could do three things, he explained in a  technical write-up : read the host's memory, crash the host, and run code on it. All three come from the same kernel flaw. Vercel said in its  report on the challen...

Someone built a tool to steal data, then decided it should scare the victim for fun. Yes, that’s an actual feature. And somehow, it fits right in with this week's security stories. The rest gets interesting in different ways. A small permission can lead to a big theft. A trusted login can hide the wrong person. Old bugs are finding new victims, familiar tools are being put to strange uses, and some flaws are so simple you wonder how nobody spotted them sooner. There's a lot more hiding in the details, including a few twists you probably wouldn't expect. Here's what made the list this week. The threats change every week. Subscribe, and we’ll alert you when each new ThreatsDay Bulletin is out.

The threat actor known as Silent Lynx has been attributed to a fresh set of attacks targeting government organizations across the Commonwealth of Independent States (CIS). The activity, observed from June 2025 through August 2026, involves four different infection chains that make use of macro-enabled documents, PS2EXE downloaders, GitHub-hosted PowerShell, and crafted WinRAR archives exploiting CVE-2025-8088 . The attacks lead to the deployment of custom reverse shells like FoalShell, Chvost, Laplas, and PickleShell that facilitate interactive remote access to compromised hosts, according to Cisco Talos and Recorded Future Insikt Group, which are tracking the campaign under the monikers UAT-6275 and TAG-193.  "UAT-6275's targeting is concentrated in Central Asia, and the wider CIS region," security researcher Ashley Shen said . "Across the reviewed campaigns, observed victims and lure themes span nine countries: Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenist...

NGINX released versions 1.30.6 and 1.31.7 on October 14 to fix five vulnerabilities, one of them present in every release since May 2005. There are three memory bugs that F5, the company behind NGINX, says could crash a worker process or possibly let an attacker run code, and each requires a specific configuration to exploit. A fourth lets an attacker forge a TLS session that could get past client-certificate checks, though F5 calls the forgery non-deterministic and beyond the attacker's control. The fifth lets an HTTP/3 client slip extra bytes into a request that NGINX passes on to a backend. None of the five was in CISA's Known Exploited Vulnerabilities catalog as of October 15, and neither NGINX nor F5 reports attacks.  NGINX rates all five medium . F5 scores the three memory bugs 9.2, Critical, on CVSS v4.0, the TLS flaw 8.3, and the HTTP/3 flaw 6.9. Which Configurations Are Exposed Every one of the five needs a directive you added: an alias...

Next.js released an  out-of-band security update  on October 14 that fixes two critical flaws allowing unauthenticated remote code execution, along with a high-severity denial-of-service flaw. One code-execution flaw is in React Server Components, and the other in librsvg, the open-source library Next.js uses through the sharp package to handle SVG images. The fixes are in Next.js 16.4.1 and 15.5.28, the current Active and Maintenance long-term support (LTS) releases. What Was Fixed The update covers three separate issues. Vercel, which develops Next.js, rated both code-execution flaws critical, each with a CVSS score of 9.5. The table lists the versions each issue affects and the version that fixes it. Issue Affected versions Fixed in Who is exposed Code execution through use cache ( GHSA-673q-mjm6-r5xr ...

Drupal core has a critical flaw in its Field UI module that could let an attacker run code on the site's server, and fixes were shipped on October 14 in Drupal 11.4.10, 11.3.19, and 10.6.19. An attacker cannot reach the flaw through core alone, the Drupal Security Team said in  its advisory . Several exploit paths exist through contributed modules, and at least one known path needs no login. Tracked as CVE-2026-108097 , the flaw sits in Field UI, the core module behind the admin pages where site builders manage fields and how they display. Drupal rates it 19 out of 25 on its own risk scale, the level the project calls critical. The advisory does not name the contributed modules that open a path to the flaw, and custom code may also expose it. Drew Webber of the Security Team and Octavio Galland are credited with reporting it. What to Do Now The fixed release for each supported branch: Drupal 11.4.x: update to  11.4.10 Drupal 11.3.x: update to  11.3.19 ...

Palo Alto Networks on Wednesday issued security updates for a high-severity flaw in PAN-OS software that has come under active exploitation. The vulnerability, tracked as CVE-2026-0322 (CVSS score: 8.6), is a case of remote code execution in the management interface. "A remote code execution (RCE) vulnerability in the management interface of Palo Alto Networks PAN-OS software enables an authenticated attacker with network access to execute arbitrary code with root privileges on the firewall," Palo Alto Networks said . The issue impacts PAN-OS software on PA-Series and VM-Series firewalls and on Panorama (virtual and M-Series). Cloud NGFW and Prisma Access are not affected by the vulnerability. Palo Alto Networks said that no special configuration is required to exploit the issue, but said the security risk can be minimized by restricting access to the management interface to only trusted internal IP addresses. "You can reduce the risk of exploitation by restr...

Threat actors are exploiting a critical security flaw in Langflow, according to an alert from Previdian. Langflow is an open-source platform that allows developers to build artificial intelligence (AI) applications and agentic workflows. In February 2025, DataStax, the parent company of Langflow, was acquired by IBM. The vulnerability in question is CVE-2026-105740 (CVSS score: 9.9), a case of authenticated remote code execution impacting versions prior to 1.9.0. "Any authenticated Langflow user can achieve Remote Code Execution (RCE) on the server by adding an MCP server with the 'stdio' transport," reads an advisory released last month. "The user-supplied command field is passed directly to bash -c "exec {command}" with zero validation, no allowlisting, and no sandboxing. The command executes immediately when the server list is fetched. Additionally, the env field allows arbitrary environment variable injection (e.g., LD_PRELOAD, PATH ove...

Singapore-based Ahsay Backup has released security updates to address two security flaws in AhsayCBS that have been exploited by bad actors to drop web shells and XMRig cryptocurrency miners. The vulnerabilities in question are CVE-2026-105133 and CVE-2026-105134 , which could be chained to sidestep authentication and execute arbitrary commands on affected systems. In a report published earlier this month, Huntress said it observed threat actors combining the two flaws to achieve unauthenticated remote code execution and deploy web shells and cryptocurrency miners on exposed systems. Although the vulnerabilities were initially assumed to be addressed in AhsayCBS versions 9.15.2.59 and 10.3.4.0 released in August 2026, the software company has now confirmed that the patches did not completely plug them. The fixes are available in the following versions - AhsayCBS v10.3.4.45 hotfix AhsayCBS v9.15.2.70 hotfix "Given the severity of these risks, we strongly urge ...

Attackers are exploiting a critical flaw in Cisco Secure Email Gateway that lets a sender with no login write files to the appliance's operating system, Cisco  said in an advisory  on Wednesday. The attacker sends an email with a crafted attachment through the gateway and, if it succeeds, could then run commands as root. The appliance filters an organization's email for spam, malware, and other threats, and only a gateway with the File Reputation service enabled and a Content Scanner Tools package older than version 25.3.0.5525 is vulnerable. The fix has been shipping since September 14 in AsyncOS 15.5.5-014 and 16.5.0-780, the builds Cisco listed as fixed in a hardening release that day, which the company now says covered this flaw. It also arrives as a Content Scanner Tools update, version 25.3.0.5525 or later, which installs without a software upgrade or a restart. Cisco found the flaw, tracked as CVE-2026-76519 (CVSS score: 9.8), in its own internal security scanni...

Attackers exploited a flaw in an optional Nextcloud app,  Collabora Online - Built-in CODE Server , to plant web shells on Nextcloud servers. Three administrators  reported the issue on GitHub , with the first logged attack on September 10. A web shell is a small file that executes any command an attacker sends via a web request, with the rights of the web server account. The flaw allows an unauthenticated request to run a command on the server, but only when the app's local document server is not running, such as during a restart or upgrade, or after a crash. Collabora fixed it in  version 26.4.303  on September 11 and on October 14 published  an advisory  with the identifier  CVE-2026-110447 , warning that turning off the app does not help: it must be updated or removed. Who Is Affected The app, published by Collabora under the package name richdocumentscode, downloads a copy of Collabora Online Development Edition (CODE) and runs it ...

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Tuesday urged organizations to take steps to immediately update their Ivanti Connect Secure (ICS) appliances and deployments to the latest version following the disclosure of an actively exploited vulnerability. The security flaw, tracked as CVE-2026-104935 (CVSS score: 8.6), is a case of authentication bypass impacting ICS versions 25.1.1.1 and prior, 25.1.2.2 and prior, and 22.8R2.4 and prior that could allow a remote unauthenticated attacker to execute arbitrary commands. "CISA is aware of cyber threat actors exploiting this zero-day authentication bypass vulnerability, which allows remote, unauthenticated execution of arbitrary commands, to conduct credential theft and data exfiltration," the agency said .  The agency has since added the flaw to its Known Exploited Vulnerabilities ( KEV ) catalog, requiring Federal Civilian Executive Branch (FCEB) agencies to apply the fixes by October 16, 2026. ...

A flaw in how curl handles HTTP/2 uploads lets a malicious server receiving an upload corrupt the client's memory, and the researcher who reported it turned that into code execution on the uploading machine. The curl project fixed it on October 14 in  curl 8.23.0 . Taking over a client needs exact knowledge of its build and memory layout, and curl expects a real attack to end in a crash instead. The flaw, a use-after-free tracked as  CVE-2026-92392 , affects curl and libcurl 8.12.0 through 8.22.0, both the command-line tool and the library that many other programs use for transfers. curl rates it High on its own four-level scale, its first High-severity flaw since the  SOCKS5 heap overflow of October 2023 . The project cut its release cycle by two weeks to ship the fix. The attack runs from the server side. The client has to upload a file of roughly 135KB over HTTP/2 to a server controlled by the attacker, and the server's certificate must pass the client's checks....

A team at security firm XBOW chained three then-unknown Google Chrome bugs into a single attack that runs code on a Windows computer when the user only loads a web page, the company said. Its researchers built the attack in six days by directing AI agents running OpenAI's publicly available GPT-5.6 Sol model. Google has since confirmed all three bugs,  fixed them , and paid XBOW its top $250,000 reward for a full Chrome exploit. The attack is a full chain: a set of bugs used together to break every layer of Chrome's protection, from a web page all the way to the computer. Chrome runs web page code inside two nested sandboxes, the barriers that stop a hacked page from reaching the rest of the machine. The chain crossed both. The result was code running outside Chrome on Windows, with no need for the user to click or download anything. All three bugs are now fixed, and XBOW says they were never used against Chrome users. The two that carry public identifiers were fixed ...

The bug was simple: the login let you choose where your sign-in code went. Proving it on a live website was the hard part. TL;DR During an authorized assessment, an AI pentesting agent found a critical authentication bypass on a major insurer's production website, on its own. One login request let the user choose where the one-time passcode went. The attack was the easy part. Proving it on a live site took web context built over a decade. The Login Worked. Then the Agent Stopped. Reflectiz's AI pentesting agent was mapping the login flow of a major insurer's production website, which has millions of users. The agent requested a login code and directed it to an email inbox it controlled. The code arrived. The login went through. Its guardrails halted the test after the login succeeded.  The agent had discovered a critical-severity authentication bypass on its own. Reflectiz reported it to the insurer. The Flaw: The Request Chose Where the Code Went ...

A flaw in Linux's vhost subsystem lets a local user read and write kernel memory at will and become root across nearly a decade of kernel versions. In one virtualization setup, it lets an untrusted virtual machine write to the host's memory and hijack the program that runs the virtual machine. The bug is tracked as  CVE-2026-74580  and named Vghost . Tencent Zhuque Lab, which found the flaw, released a fix on August 3 and published a full write-up on October 12 with working demos of both attacks. There is no public sign it has been exploited yet. vhost is the part of the Linux kernel that speeds up network and other input/output for virtual machines and containers. A local user reaches it by opening a device node, usually /dev/vhost-net or /dev/vhost-vsock. On the host, the flaw gives an unprivileged user a reliable way to read and write any kernel address, bypass KASLR, and escalate to root. The attack is deterministic: it needs no memory grooming and ...

Security researchers ran their own code inside a protected part of Windows that is meant to stay sealed off even when the rest of the computer is taken over. The protected area is a VBS enclave , an isolated slice of memory the operating system uses to guard secrets, and the one they broke into handles passwords for a Windows anti-phishing feature. The work was done in a lab as a proof of concept, has not been seen in real attacks, and Microsoft fixed the flaw in its September 8, 2026 update. The flaw is tracked as  CVE-2026-83498 . Microsoft rates it an elevation-of-privilege issue, Critical, with a CVSS score of 7.8, and says it has not been exploited and was not publicly known before the fix. Microsoft also says it found the same issue internally. The research, by the security firm  Doyensec , was published October 13, more than a month after the patch. A VBS enclave is a signed library that a normal Windows program loads but cannot read or change once it is runnin...

Microsoft on Tuesday shattered its own Patch Tuesday record by shipping patches for a whopping 1,413 vulnerabilities , including one that it said has come under active exploitation. These include 1,102 flaws in Windows, 134 in Office, 61 in Developer Tools, 36 in SharePoint Server, and 22 in SQL Server. Of these, more than 670 relate to privilege escalation, followed by over 300 remote code execution flaws and 250 information disclosure flaws. Over 70 flaws are rated Critical in severity. "Hundreds of CVEs in a single release used to be the exception; now it's the baseline," Dustin Childs, head of Threat Awareness at the Zero Day Initiative (ZDI), said . "Is AI to blame? Partly. It's accelerating bug-hunting on both sides of the fence, so vendors are finding (and fixing) more flaws, and researchers are finding them faster too." "But AI isn't creating these bugs out of thin air; it's just shortening the time between a vulnerability existin...

A flaw in Docker Hub, the registry where container images are published and downloaded, let one user push, pull, or delete images as another user. Docker fixed the flaw on September 30 and says it found no evidence that anyone exploited it. The flaw was in the feature that  converts a personal account  into an organization, Docker said in a  security advisory  on October 12. Conversion transferred the account's personal access tokens (PATs) to the user designated as the organization's owner. A PAT is used in place of a password in the registry, and the person who created each token can still use it. The access was limited to the registry. It did not reach the Docker Hub web interface, and it could not be used to change a password, email address, or two-factor settings, or to take over an account. Docker tracks the flaw as CVE-2026-105445 and rated it critical. The  CVE record  it published on October 13 gives the flaw a CVSS 4.0 score of 9.4. The ...

An attacker chained three zero-day flaws in Ivanti Connect Secure, a VPN appliance, to run commands as root without logging in, security firm  Volexity said  on October 13. Ivanti has released fixes for two of the flaws and told customers on affected versions to "act immediately." A fix for the third is still pending, according to Volexity. Volexity, which reported the flaws to Ivanti, found the attack on one customer's appliance. The appliance was fully patched at the time and running version 22.8R2.4. The attacker, which Volexity tracks as UTA0576, began exploiting it on October 3. Ivanti said  on October 13 that it is aware of "limited exploitation in the wild." The first two flaws are an authentication bypass and a remote code execution flaw, tracked together as  CVE-2026-104935 . Together they let an attacker run code as the appliance's cgi-server user, and the third flaw, a privilege escalation, raises that to root, Volexity said. The CVE reco...