Last updated: September 29, 2026 at 8:42 AM UTC
All 891 Vulnerability 357 Breach 144 Threat 383 Defense 7
Tag: privilege-escalation (54 articles)Clear

OpenClaw 'Claw Chain': four sandbox-escape and priv-esc flaws on ~180K public AI agent instances (patched 2026.4.22)

Researchers at Cyera have disclosed a chain of four vulnerabilities in OpenClaw, an open-source autonomous AI agent platform that Nvidia and Tencent have built enterprise products on top of. The chain - CVE-2026-44112 (CVSS 9.6), CVE-2026-44113, CVE-2026-44115, and CVE-2026-44118 - lets an attacker who can influence the agent's input (through a malicious plugin, prompt injection, or compromised tool output) break out of the OpenShell sandbox, read environment-stored API keys, elevate to owner-level privileges, and write persistent backdoors. Each step looks like normal agent behavior. Shodan and Zoomeye between them counted 65,000 to 180,000 public OpenClaw instances earlier in May. All flaws are fixed in OpenClaw 2026.4.22.

Check
Inventory OpenClaw, NemoClaw, and ClawPro deployments. Check installed version via --version or /api/version. Search agent logs for unexpected symlink creation or env-var reads inside heredocs.
Affected
All OpenClaw releases prior to version 2026.4.22 (April 23, 2026). Nvidia NemoClaw and Tencent ClawPro builds derived from older OpenClaw cores inherit the same flaws unless rebased.
Fix
Update to OpenClaw 2026.4.22 or later. Until then, scope the OpenShell sandbox to a read-only filesystem, strip secrets from the agent's environment, and route egress through a logging proxy.

MiniPlasma Windows zero-day: working PoC gives SYSTEM on fully patched Windows 11 via cldflt.sys driver

A researcher who goes by Chaotic Eclipse has dropped working proof-of-concept code on GitHub for a Windows local privilege escalation that gives SYSTEM access on fully patched Windows 11 Pro and Windows Server 2025. The bug lives in the Cloud Filter driver cldflt.sys and is, the researcher says, the same flaw Google Project Zero reported to Microsoft as CVE-2020-17103 in 2020, which Microsoft said it fixed in December 2020. The original Google PoC works unmodified. May 2026 Patch Tuesday updates do not stop it. The same researcher has dropped several other Windows zero-days in recent weeks, all of which were quickly seen in real attacks.

Check
Inventory Windows 11 and Server 2022/2025 endpoints. Hunt SIEM for unexpected SYSTEM-context cmd.exe spawns or new processes launched from standard user sessions touching cldflt.sys.
Affected
Microsoft Windows 11 Pro and Windows Server 2025 with May 2026 Patch Tuesday updates applied. The researcher claims all Windows versions are likely affected.
Fix
No patch available. Block execution of the public MiniPlasma binary by hash in EDR. Tighten local user privileges and restrict admin sessions on multi-user endpoints until Microsoft ships a fix.

Azure Backup for AKS lets low-privileged Backup Contributors gain cluster-admin, Microsoft blocked CVE (VU#284781)

Microsoft has refused to issue a CVE for what an outside researcher and the CERT Coordination Center both describe as a privilege escalation in Azure Backup for Azure Kubernetes Service. The flaw lets a user holding only the low-privileged 'Backup Contributor' Azure role gain cluster-admin on AKS clusters, which Microsoft dismissed by saying the attacker 'already held administrator access.' CERT/CC validated the bug and tracked it as VU#284781. The researcher says Microsoft also tried to get MITRE to reject the submission as 'AI-generated content,' then quietly added new permission checks, suggesting a silent patch even as Microsoft says 'no product changes were made.'

Check
Audit Azure RBAC assignments on subscriptions hosting AKS clusters. Identify any users holding the 'Backup Contributor' role and verify they were intended to hold cluster-admin rights.
Affected
Azure Kubernetes Service clusters with Azure Backup for AKS enabled, where the 'Backup Contributor' role has been assigned. No CVE issued; CERT tracking ID VU#284781.
Fix
Restrict the 'Backup Contributor' role to trusted operators only. No vendor patch acknowledged; rely on least-privilege RBAC until Microsoft confirms a fix. Monitor MSRC for updates.

cPanel patches three new flaws including two that let authenticated users run arbitrary Perl code on the server - on top of the active 'Sorry' ransomware wave still hitting unpatched systems

cPanel released patches Friday for three new vulnerabilities. The two worst (CVE-2026-29202 and CVE-2026-29203, both CVSS 8.8) let authenticated users execute arbitrary Perl code through the create_user API or escalate privileges via unsafe symlink chmod. The third (CVE-2026-29201, CVSS 4.3) lets authenticated users read arbitrary files. No exploitation observed yet. The disclosure lands while attackers are still mass-exploiting CVE-2026-41940 to deploy 'Sorry' ransomware against cPanel hosts, including a wave targeting government agencies and MSPs (covered May 5). Hosting providers face a compounding patch burden.

Check
Inventory cPanel and WHM versions. Check whether any servers are still on builds before the May 9 release. Search authentication logs for use of the create_user API or feature::LOADFEATUREFILE adminbin call by accounts that don't normally use them.
Affected
cPanel and WHM versions before 11.136.0.9, 11.134.0.25, 11.132.0.31, 11.130.0.22, 11.126.0.58, 11.124.0.37, 11.118.0.66, 11.110.0.116/117, 11.102.0.41, 11.94.0.30, 11.86.0.43. Legacy CentOS 6 and CloudLinux 6 customers must patch to 110.0.114. The CVSS 8.8 flaws require authentication, so internet-facing cPanel servers with weak password policies face acute risk.
Fix
Patch cPanel to a fixed version per the May 9 advisory. Apply the new patches alongside the existing CVE-2026-41940 (Sorry ransomware) fix. Tighten cPanel user account password policies and enforce 2FA for any account with API access. Restrict cPanel ports (2082-2087, 2095-2096) to trusted IPs to limit pre-auth attack surface.

Brand-new Linux 'Dirty Frag' bug lets any local user become root on every major distribution - PoC exploit is public, no patches yet

Researcher Hyunwoo Kim disclosed Dirty Frag yesterday after an unrelated third party broke the embargo five days early. The flaw chains two Linux kernel page-cache write bugs (xfrm-ESP and RxRPC) to give any local user root access on every major distribution - Ubuntu, RHEL, CentOS Stream, AlmaLinux, openSUSE Tumbleweed, Fedora. Like Dirty Pipe and last week's Copy Fail, it's a deterministic logic bug with no race condition required and no kernel panic on failure. PoC is public on GitHub. The ESP variant patch was merged into the netdev tree on May 7 but distribution kernels remain unpatched. No CVE assigned yet because the embargo broke early.

Check
Inventory Linux servers, container hosts, CI runners, and Kubernetes nodes that allow shell access or run untrusted code. Check whether esp4, esp6, and rxrpc kernel modules are loaded with 'lsmod | grep -E "esp4|esp6|rxrpc"'.
Affected
Every Linux distribution with kernel 4.10+ (ESP variant) and 5.x+ (RxRPC variant). All major distros confirmed: Ubuntu, RHEL, CentOS Stream, AlmaLinux, openSUSE Tumbleweed, Fedora. Acute risk: shared-kernel multi-tenant environments (Kubernetes nodes, container hosts), CI/CD runners executing untrusted PR code. Firecracker microVMs and gVisor are not affected.
Fix
Blacklist vulnerable modules: 'sh -c "printf \'install esp4 /bin/false\\ninstall esp6 /bin/false\\ninstall rxrpc /bin/false\\n\' > /etc/modprobe.d/dirtyfrag.conf; rmmod esp4 esp6 rxrpc 2>/dev/null; true"'. This breaks IPsec VPNs and AFS filesystems but stops the exploit. Apply distribution kernel patches as soon as they ship - AlmaLinux has early test patches. Treat container boundaries as broken until patched.

9-year-old Linux kernel bug 'Copy Fail' lets any user with shell access become root in seconds - works on every major distribution since 2017 (CVE-2026-31431)

Researchers at Theori and Xint disclosed Copy Fail yesterday, a Linux kernel bug introduced in 2017 that lets any unprivileged user with shell access become root in seconds. The exploit is a 732-byte Python script that works without version-specific tweaks on every major Linux distribution since 2017 - Ubuntu, Amazon Linux, RHEL, SUSE. Unlike previous kernel bugs (Dirty Cow, Dirty Pipe), Copy Fail has no race condition and no per-kernel offsets. It also leaves no trace on disk because it only modifies the in-memory page cache. The bug was found using AI-assisted reverse engineering and has been hiding in the open for nearly nine years.

Check
Update the kernel on every Linux server, container host, and CI runner you operate today, especially anything that runs untrusted code or hosts multiple tenants.
Affected
Every Linux distribution since 2017 with kernel 4.14 or later. CVE-2026-31431, CVSS 7.8. Acute risk: shared-kernel multi-tenant environments (Kubernetes nodes, Docker hosts), CI/CD runners that execute untrusted PR code (GitHub Actions self-hosted, GitLab runners, Jenkins agents), notebook hosts, and anything using Linux containers as a security boundary. Firecracker microVMs and gVisor are not affected.
Fix
Apply the kernel update from your distribution that includes commit a664bf3d603d. Until patched, blacklist the algif_aead module: 'echo "install algif_aead /bin/false" > /etc/modprobe.d/disable-algif.conf' then 'rmmod algif_aead'. The disable does not break dm-crypt, kTLS, IPsec, or SSH. For multi-tenant Kubernetes clusters, treat container boundaries as broken until patched.

Microsoft patches Entra ID role flaw that let a low-privileged service account impersonate any service principal in your tenant

Microsoft quietly patched a privilege escalation flaw in Entra ID (formerly Azure AD) that let an attacker with a low-privileged service account take over any service principal in the same tenant - including high-value ones with admin consent grants. The bug was in how Entra ID validated role assignments during certain API calls: the validator checked whether the caller had any role on a service principal but didn't check whether that role authorized the specific action. Microsoft fixed the flaw on the back end, so customers don't need a patch - but the takeover scenario means anyone who exploited it before the fix could have created persistent backdoors via OAuth grants.

Check
Audit your Entra ID tenant this week for unfamiliar service principals, unexpected admin consent grants, and OAuth tokens issued to apps you don't recognize.
Affected
Microsoft Entra ID tenants with multiple service principals where any low-privileged account had role assignments on those service principals. The fix is server-side, so you don't need to apply a patch - but you do need to assume any attacker with foothold access before the fix could have abused this to escalate.
Fix
Run a Microsoft Graph audit on your tenant: list all service principals, OAuth grants, and app role assignments created since January 2026. Investigate any unfamiliar app, any grant from a service account, and any service principal whose roles changed unexpectedly. Revoke and re-issue admin consent for high-privilege apps. Enable audit logging for application registrations.

New 'PhantomRPC' bug lets any low-privileged Windows process become SYSTEM - all Windows versions affected, no patch from Microsoft

Kaspersky disclosed PhantomRPC at Black Hat Asia on April 24, an architectural flaw in how Windows handles a core internal communication system called RPC (Remote Procedure Call). When a privileged Windows process tries to talk to an RPC server that isn't running, the operating system doesn't check whether the thing answering is the real one - so a low-privileged attacker can stand up a fake RPC server, intercept the call, and inherit SYSTEM-level access. All Windows versions are affected. Kaspersky demonstrated five different exploitation paths and published the research tools on GitHub. Microsoft has not released a patch.

Check
Treat any unprivileged Windows process as a potential SYSTEM-escalation foothold and tighten EDR rules around suspicious RPC server registrations until Microsoft patches.
Affected
All Windows versions including Windows 10, Windows 11, and Windows Server, plus older builds. Acute risk on multi-user systems, terminal servers, and any host where untrusted code might run as a low-privileged service account such as NETWORK SERVICE - those are the easiest launch points for the technique.
Fix
There is no Microsoft patch yet. Use Kaspersky's public PhantomRPC tooling to audit your environment for exploitable RPC patterns. Tighten EDR detection on processes registering RPC endpoints with privileged-service UUIDs. On terminal servers, limit which low-privileged accounts can run code. Watch Microsoft Security Response Center for updates over the coming weeks.

CISA adds actively-exploited Microsoft Defender 'BlueHammer' flaw to KEV as two sibling zero-days (RedSun, UnDefend) remain unpatched (CVE-2026-33825)

CISA added CVE-2026-33825 to its Known Exploited Vulnerabilities catalog on April 23 with a May 7 federal patch deadline. The flaw, nicknamed BlueHammer, is a race condition in Windows Defender's file-remediation logic that lets an unprivileged local attacker overwrite arbitrary files on disk and escalate to SYSTEM on fully-patched Windows 10 and Windows 11 hosts. It was patched in Microsoft's April 8 Patch Tuesday but a working proof-of-concept had already been published to GitHub by a researcher called 'Chaotic Eclipse' on April 7, before the fix shipped. Huntress Labs saw in-the-wild exploitation from April 10, with attackers also picking up two sibling Defender zero-days the same researcher leaked: RedSun (another local privilege escalation) and UnDefend (a denial-of-service that blocks Defender from pulling security definition updates, effectively disarming the EDR). Those two still have no Microsoft patch. The combination - a working privilege-escalation path plus an unpatched technique to silently cripple Defender itself - makes this a priority hunt, not just a priority patch.

Check
Verify that every Windows 10 and Windows 11 endpoint in your fleet has the April 2026 Patch Tuesday update installed and then hunt for the BlueHammer/RedSun/UnDefend technique patterns in your EDR telemetry.
Affected
Windows 10 and Windows 11 endpoints that have not installed the April 8, 2026 Patch Tuesday cumulative update. Note that patching closes BlueHammer (CVE-2026-33825) only - RedSun and UnDefend remain unpatched at time of writing, so patched hosts are still exposed to local privilege escalation via RedSun and to Defender disablement via UnDefend.
Fix
Deploy the April 2026 Patch Tuesday update (which addresses CVE-2026-33825) to every Windows endpoint and verify coverage against MDM or configuration-management inventory rather than trusting WSUS compliance alone. For the two unpatched sibling flaws, tighten EDR rules to alert on: anomalous file writes to Defender-controlled paths, unexpected changes to Defender signature update behavior, and any process attempting to stop or starve MsMpEng.exe. Treat any host where Defender has not received a signature update in over 48 hours as suspicious until proven otherwise. Review Huntress's public IoCs for the three techniques.

Microsoft ships emergency out-of-band patch for critical ASP.NET Core authentication cookie forgery flaw (CVE-2026-40372)

Microsoft released out-of-band security updates for a critical ASP.NET Core Data Protection flaw that lets unauthenticated attackers forge authentication cookies and escalate to SYSTEM privileges. The bug (CVE-2026-40372) is a regression introduced in the April 2026 Patch Tuesday: the Microsoft.AspNetCore.DataProtection 10.0.0 through 10.0.6 NuGet packages compute the HMAC validation tag (the cryptographic signature that proves a cookie has not been tampered with) over the wrong bytes of the payload and then discard the hash in some cases. The broken check means attackers can forge payloads that pass DataProtection's authenticity checks and decrypt previously-protected data in auth cookies, antiforgery tokens, TempData, and OIDC state. Microsoft noticed the flaw only after users reported decryption failures in their apps after installing the .NET 10.0.6 update. Critical operational detail: updating to 10.0.7 stops future forgeries, but any tokens an attacker already got the app to legitimately sign during the vulnerable window (session refresh tokens, API keys, password reset links) remain valid forever unless you rotate the DataProtection key ring. Patching alone is not enough.

Check
Check whether any ASP.NET Core application you run is on the Microsoft.AspNetCore.DataProtection NuGet package versions 10.0.0 through 10.0.6.
Affected
Microsoft.AspNetCore.DataProtection NuGet package versions 10.0.0 through 10.0.6 (shipped as part of .NET 10.0.0 through .NET 10.0.6).
Fix
Update the Microsoft.AspNetCore.DataProtection package to 10.0.7 and redeploy. Critically, also rotate the DataProtection key ring after patching - any legitimately-signed tokens (session refresh, API keys, password reset links) issued to an attacker during the vulnerable window remain valid until the key ring is rotated. Audit auth logs from April 14 through April 22 for suspicious token issuance.