CVE-2026-90162: Linux kernel · ksmbd: defer publishing granted locks to prevent UAF/double-free race
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 8.8 High.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 50% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 17 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 defers publishing granted locks until the entire batch of lock requests is processed successfully, preventing the race condition. Users should apply the official kernel updates that include this fix. Since this is a kernel vulnerability, upgrading to patched kernel versions is the recommended remediation.
Description
A use-after-free and double-free vulnerability was resolved in the Linux kernel's ksmbd component. The issue involved premature publishing of granted locks to connection-wide and file-wide lists before completing validation of all lock requests in a batch. This could lead to concurrent unlock requests freeing the same lock object twice, causing memory corruption. The fix defers publishing granted locks until the entire batch is successfully processed, eliminating the race condition.
References
- nvd.nist.gov/vuln/detail/CVE-2026-90162 (opens in a new tab)
- git.kernel.org/stable/c/29f74f0f2e6df3b393b7b66e810136d0c64e3c59 (opens in a new tab)
- git.kernel.org/stable/c/a1d26dfb32919088e3638dca01068df3c4507433 (opens in a new tab)
- ubuntu.com/security/CVE-2026-90162 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-90162 (opens in a new tab)
- git.kernel.org/linus/29f74f0f2e6df3b393b7b66e810136d0c64e3c59 (opens in a new tab)
- git.kernel.org/stable/c/65f54ed0289e9a57e6c60b14347ccea4c318f1fc (opens in a new tab)
- git.kernel.org/stable/c/b68d4bb6b03a667c305626bd2c242fd162bac17e (opens in a new tab)
- git.kernel.org/stable/c/ff6870cf3b7eccc69d03cbb6f23e3995d96e9a8d (opens in a new tab)