Kernel-level use-after-free in the ubiquitous Linux audit subsystem can crash systems or enable local privilege escalation across servers, endpoints, containers — wide organizational impact.
CVE-2026-89643
Linux audit bug causes use-after-free enabling local kernel compromise or crash
Is CVE-2026-89643 being exploited?
Not confirmed. CVE-2026-89643 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.70% probability of exploitation in the next 30 days.
How severe is CVE-2026-89643?
CVE-2026-89643 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-89643?
Yes. A fix has been recorded for CVE-2026-89643. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-89643 affect?
CVE-2026-89643 affects Linux kernel (audit subsystem), Major Linux distributions (Ubuntu, RHEL, Debian, SUSE), Cloud VMs and containers running affected kernels, Embedded devices using affected kernels. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-89643?
Apply vendor kernel updates immediately and reboot affected systems
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Local attacker can trigger a use-after-free in audit rule autoremove, causing kernel crash or enabling local privilege escalation/arbitrary kernel code execution.
Immediate action required
- affected>= 34d99af52ad40bd498ba66970579a5bc1fb1a3bc and < cf37b61b5420fd4600fe78cf8c24da6e4d9bfe28
- affected>= 34d99af52ad40bd498ba66970579a5bc1fb1a3bc and < 636a99bab36ba27515363d325866c0273ac83b3e
- affected>= 34d99af52ad40bd498ba66970579a5bc1fb1a3bc and < 583cf579b32d99e3fe4e9c8ecc4d852e3708fbec
- affected>= 34d99af52ad40bd498ba66970579a5bc1fb1a3bc and < 783f0f0974c156aca630f4ffff248671082a098d
- affected4.3
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.