Last updated: August 19, 2026 at 1:47 AM UTC
All 741 Vulnerability 286 Breach 129 Threat 319 Defense 7
Tag: privilege-escalation (41 articles)Clear

Ransomware gangs now exploit a Windows Task Host flaw to gain SYSTEM

CISA confirmed that ransomware groups are now exploiting a Windows Task Host privilege-escalation flaw that has been flagged as actively exploited since April. Tracked as CVE-2025-60710 and scored 7.8, it is a link-following weakness in the component that runs background scheduled tasks as SYSTEM: a local attacker with only basic user rights can use a junction on a user-writable path to make a SYSTEM-level task act on files it should not, escalating to full control. Microsoft patched it in November 2025, and it affects Windows 11 and Server 2025. Privilege escalation like this is exactly what ransomware operators need to disable defenses and spread after gaining an initial foothold.

Check
Confirm the November 2025 update for this flaw is deployed across Windows 11 and Windows Server 2025 systems, prioritizing any that still lack it, since ransomware crews are now using it.
Affected
Windows 11 and Windows Server 2025 systems missing the November 2025 patch (CVE-2025-60710); a local attacker with basic rights can escalate to SYSTEM, and ransomware groups are actively exploiting it.
Fix
Apply the patch, prioritize privilege-escalation fixes in your patching since they enable ransomware to spread, monitor for junction abuse and unexpected SYSTEM-level file operations, and limit local footholds through least privilege.

Red Hat cluster management flaw lets a namespace editor become cluster admin

Red Hat disclosed a critical flaw in its Advanced Cluster Management for Kubernetes that lets a user with only namespace-level edit rights escalate to full cluster administrator. Tracked as CVE-2026-10090 and scored 9.9, the bug is in the application subscription controller: a low-privileged user can create a channel pointing to a Helm repository they control, then a subscription referencing it, and the controller deploys the chart using its own elevated permissions without checking the requester's authorization. It is a confused-deputy problem that crosses the namespace-to-cluster boundary. Because namespace edit access is often granted broadly to developers, many multi-tenant clusters could be exposed, and no fix was available at disclosure.

Check
Identify Advanced Cluster Management hub namespaces where non-administrators hold edit rights, restrict those permissions, and monitor for unexpected channel and subscription objects pointing to external Helm repositories.
Affected
Organizations running Red Hat Advanced Cluster Management for Kubernetes (CVE-2026-10090); a user with namespace edit rights on the hub can reach full cluster-admin and access secrets, with no fix yet.
Fix
Tighten who holds namespace edit access on ACM hubs, watch for suspicious channel and subscription resources, and apply Red Hat's fix as soon as it ships, since no mitigation fully substitutes.

18-year-old Linux SCTP flaw gives local root and can escape containers

Tencent researchers disclosed SCTPhantom, a use-after-free flaw in the Linux kernel's SCTP networking code that lets a local user gain root and, in some configurations, escape a container to the host. Tracked as CVE-2026-64564, the bug is in the protocol's dynamic address reconfiguration handling and traces to code introduced around 2008, making it roughly 18 years old. It is local rather than remote and needs SCTP reachable on the target, which limits exposure, but where those conditions hold the researchers gained root on several major distributions. It was found by an AI-assisted kernel research pipeline, the latest long-dormant kernel bug surfaced that way this year.

Check
Update to a fixed kernel, checking your distribution's tracker rather than the version string since vendors backport, and where SCTP is not needed, block the module to remove the attack surface.
Affected
Linux systems with SCTP reachable and an unpatched kernel (CVE-2026-64564); a local user can gain root, and in some container configurations escape to the host, though remote exploitation is not possible.
Fix
Apply the distribution kernel update and reboot, disable the SCTP module where unused, and tighten container policies that grant network and packet-socket capabilities to untrusted workloads.

OVSwrap kernel flaw gives local users root on most Linux distributions

A researcher disclosed OVSwrap, a Linux kernel flaw in the Open vSwitch datapath that lets an ordinary local user gain root, and published a working exploit covering roughly 800 builds. Tracked as CVE-2026-64531, it is an integer wraparound in how Open vSwitch handles internally generated network action streams, giving a deterministic memory-corruption path. The attacker needs no existing switch, no running daemon, and no special privileges: where unprivileged user namespaces are enabled, they create a private namespace, gain network capabilities inside it, and reach the vulnerable code. The module can even auto-load on demand, so an empty module list does not mean safety. Default configurations of most major distributions tested as exploitable.

Check
Install the patched vendor kernel, which upstream fixed on July 24, and where you cannot patch immediately, disable unprivileged user namespaces to cut off the main path to the flaw.
Affected
Most default-configured Linux systems with the Open vSwitch module available and unprivileged user namespaces enabled (CVE-2026-64531); an ordinary local user can corrupt kernel memory and gain root, with a public exploit available.
Fix
Apply patched kernels and reboot, restrict unprivileged user namespaces where feasible, and prioritize shared and multi-tenant hosts, since any local foothold from another flaw or stolen access can escalate to full control.

Critical cPanel flaw lets a hosting customer gain database administrator access

cPanel patched a critical flaw that lets an ordinary hosting customer escalate to full database administrator access, running SQL as the database root user. Tracked as CVE-2026-58048 with a score of 9.4, the bug is significant on shared hosting, where many customers use one database server: administrator access there can expose or alter other tenants' data, and depending on the operating system and database configuration, cPanel warns it may extend to operating-system-level compromise. cPanel is one of the most widely deployed web hosting control panels, so the flaw affects a large number of shared and reseller hosting environments. Fixes shipped across several release tiers.

Check
Update cPanel to a patched build for your release tier, prioritizing shared and reseller servers, and if you host with a provider, confirm they have applied the fix.
Affected
Providers and customers on unpatched cPanel servers (CVE-2026-58048); a hosting customer can gain database root access, reaching other tenants' data and potentially the underlying operating system on shared infrastructure.
Fix
Apply cPanel's patched builds, apply the vendor's interim mitigation where immediate updating is not possible, review database accounts and logs for unauthorized administrator use, and segment tenants where feasible.

Nine year old Linux kernel flaw gives local users root on default RHEL installs

Qualys disclosed RefluXFS, a race condition in the Linux kernel's XFS copy-on-write path that lets an ordinary local user overwrite protected files and take root. Tracked as CVE-2026-64600, it triggers when two concurrent direct writes target the same reflinked file: the kernel briefly drops its inode lock, and a second writer can make the first write land on a stale block. The overwrite happens at the block layer, so ownership, permissions, timestamps, and the setuid bit stay untouched and no kernel log entry appears. Qualys reports it works with SELinux enforcing and estimates over 16 million affected systems.

Check
Update kernels on hosts using XFS with reflink enabled, then reboot to apply, and prioritize shared systems where untrusted users or workloads already have local execution.
Affected
Systems running Linux 4.11 or later with a reflink enabled XFS filesystem (CVE-2026-64600), which is the default on Red Hat Enterprise Linux and derivatives, Oracle Linux, Amazon Linux, and Fedora Server.
Fix
Install vendor backported kernels and reboot, since the fix merged upstream on July 16. Debian, Ubuntu, and SUSE are exposed only where an administrator chose XFS with reflink at install.

Ubuntu snap-confine flaw turns any local account into root on default desktops

Qualys disclosed a privilege escalation flaw in snap-confine, the component that builds the sandbox for every snap application. CVE-2026-8933, rated 7.8, affects default installations of Ubuntu Desktop 24.04, 25.10, and 26.04, and stems from a 2025 hardening change that moved snap-confine from a setuid root binary to a capabilities model, introducing a race during sandbox setup. An attacker mounts a filesystem over the temporary scratch directory, plants a symlink so a privileged write lands on another file, then drops a udev rule that makes a system service run commands as root. Fixes shipped July 21.

Check
Update snapd across desktops and developer workstations, and verify the installed snapd version on each machine rather than assuming an older release or prior patching leaves it unaffected.
Affected
Default installations of Ubuntu Desktop 24.04, 25.10, and 26.04 (CVE-2026-8933); anyone with local execution, whether from stolen credentials or a malicious app, can escalate to full root control of the host.
Fix
Install the updated snapd packages, limit local shell access to trusted users until patched, and treat local privilege escalation as urgent since footholds on endpoints are routinely obtained through phishing.

Researcher drops unpatched Windows privilege-escalation zero-day right after Patch Tuesday

Less than an hour after Microsoft's July Patch Tuesday, the researcher known as Nightmare Eclipse published a proof-of-concept for LegacyHive, a Windows privilege-escalation flaw that works on fully updated systems. It abuses the Windows User Profile Service to let a standard user load another user's registry hive, including an administrator's, into their own profile, a useful stepping stone for an attacker who already has a foothold. There is no CVE, advisory, or patch. The public proof-of-concept was deliberately stripped down, needing extra credentials, but the researcher says the original had no such limits. Given this researcher's flaws have been weaponized quickly before, defenders should not wait for a fix.

Check
Since there is no patch, limit who can create local standard-user accounts, and monitor the Windows User Profile Service for unexpected registry hive loads and access to NTUSER.DAT and UsrClass.dat files.
Affected
Fully patched Windows desktops and servers; an attacker with a standard-user foothold and credentials can use LegacyHive to load another user's registry hive and help escalate privileges, with no fix yet.
Fix
Apply Microsoft's fix as soon as it ships, and until then restrict local account creation, watch for suspicious profile-service and registry activity, and validate the proof-of-concept only in isolated test environments.

15-year-old GhostLock flaw gives any Linux user root and escapes containers

Researchers at Nebula Security disclosed GhostLock, a Linux kernel flaw that lets any logged-in user gain full root on an unpatched machine, and it also escapes containers. Tracked as CVE-2026-43499, the bug has shipped by default in essentially every mainstream distribution since 2011 and needs no special permissions or network access; ordinary threading calls from any local program are enough. Nebula built a working exploit it says is 97 percent reliable and published the code, though no in-the-wild use is known yet. There is no full workaround, patch availability is uneven across distributions, and one earlier fix introduced a separate crash bug, so confirm the fixed package version.

Check
Check Linux systems, especially shared machines, cloud servers, containers, and CI runners, against your distribution's GhostLock advisory, and confirm the fixed package version is installed rather than assuming a patch is present.
Affected
Almost all Linux systems on unpatched kernels (CVE-2026-43499), since the flawed code has shipped by default since 2011; any local user can gain root and escape containers, with public exploit code available.
Fix
Apply your distribution's kernel update once the final version is available, prioritizing containers, CI runners, and multi-tenant hosts. The build options RANDOMIZE_KSTACK_OFFSET and STATIC_USERMODE_HELPER make exploitation harder but are not fixes.

Microsoft patches RoguePlanet Defender flaw that handed attackers SYSTEM access

Microsoft has patched RoguePlanet, a Microsoft Defender flaw that a public proof-of-concept had been exploiting since June to gain SYSTEM privileges on fully updated Windows machines. Tracked as CVE-2026-50656, the bug is a race condition in Defender's scanning engine: a low-privileged attacker who already has code running on a host can win a timing window to spawn a command shell as SYSTEM, and the public exploit worked whether or not real-time protection was enabled. It does not provide initial access, but it turns any foothold into full local control, useful for disabling defenses, stealing credentials, and moving laterally. It is the fourth Defender flaw disclosed by the same researcher this year.

Check
Confirm that Microsoft Defender's engine and platform updates addressing RoguePlanet have reached all Windows systems, since these updates usually arrive automatically, and verify current versions across the fleet rather than assuming.
Affected
Windows 10 and 11 systems, including fully patched ones, before the RoguePlanet fix (CVE-2026-50656); an attacker with any local code execution could escalate to SYSTEM through the Defender scanning engine.
Fix
Ensure the Defender update for CVE-2026-50656 is applied everywhere and verify engine versions, harden the steps leading to local code execution with application control, and limit local admin rights to contain compromise.