CVE-2026-89763: Linux kernel · KEYS: trusted: Fix TPM teardown ordering
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/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 is available that corrects the teardown order by moving unregister_key_type() before releasing the TPM chip reference and freeing the digest array. Users should apply the official patches or updated kernel versions that include this fix. Since this is a Linux kernel vulnerability, upgrading to patched kernel versions is the recommended remediation.
Description
A use-after-free vulnerability in the Linux kernel's trusted key subsystem related to TPM teardown ordering has been resolved. The issue occurs because trusted_tpm_exit() drops the TPM chip reference and frees the digest array before unregistering the trusted key type, allowing concurrent operations to access freed memory. This can lead to memory corruption and potential system instability. The flaw affects multiple specific Linux kernel versions. The vulnerability has a CVSS score of 7.8, indicating high impact on confidentiality, integrity, and availability.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89763 (opens in a new tab)
- git.kernel.org/stable/c/2f7541afbc57fe9d26769a22c31d8ce8790c9a19 (opens in a new tab)
- git.kernel.org/stable/c/5e2d672280d97d83de43031d93761b12dadd7b8a (opens in a new tab)
- git.kernel.org/stable/c/753c978f2400f9783eb524842a975d3ac950d511 (opens in a new tab)
- ubuntu.com/security/CVE-2026-89763 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89763 (opens in a new tab)
- git.kernel.org/linus/5e2d672280d97d83de43031d93761b12dadd7b8a (opens in a new tab)