CVE-2026-89643: Linux kernel · audit: avoid dropping live tree ref on fsnotify rule autoremove
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.8 Critical.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.7% chance of exploitation in 30 days – higher than 53% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 11 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix for this vulnerability has been implemented in the Linux kernel. Users should apply the official patches or update to fixed versions of the linux-aws kernel to remediate this issue. Since this is not a cloud service, manual patching is required. Check vendor advisories for the latest updates and apply them promptly.
Description
A vulnerability in the Linux kernel's audit subsystem could lead to use-after-free conditions due to improper handling of tree references during fsnotify rule autoremove operations. This flaw affects specific linux-aws kernel versions and has been resolved by adjusting reference management in audit_del_rule() and audit_rule_change(). The vulnerability has a high CVSS score of 9.8, indicating critical impact on confidentiality, integrity, and availability.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89643 (opens in a new tab)
- git.kernel.org/stable/c/583cf579b32d99e3fe4e9c8ecc4d852e3708fbec (opens in a new tab)
- git.kernel.org/stable/c/636a99bab36ba27515363d325866c0273ac83b3e (opens in a new tab)
- git.kernel.org/stable/c/783f0f0974c156aca630f4ffff248671082a098d (opens in a new tab)
- git.kernel.org/stable/c/cf37b61b5420fd4600fe78cf8c24da6e4d9bfe28 (opens in a new tab)
- ubuntu.com/security/CVE-2026-89643 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89643 (opens in a new tab)
- git.kernel.org/linus/783f0f0974c156aca630f4ffff248671082a098d (opens in a new tab)