Skip to main content
VulnerabilityPublished Updated

CVE-2026-90036: Linux kernel · NFSD: Prevent client use-after-free during blocked-lock reaping

Affects Linux kernelSource CVE Database V5

0

Not known to be exploited · CVSS 9.8 Critical · fixed in cd489b03587378645fe0d20142a33f1ed60bac98 : patch Linux kernel as a priority.

Data as of 26 Oct 2026, 19:56 UTC

CVSS 3.1 base score
9.8Critical
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.4% chance of exploitation in 30 days – higher than 41% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available – fixed in cd489b03587378645fe0d20142a33f1ed60bac98, 9026932ac8be4d0ae01db47f23619a98cc57b671, 7081224a59a0ca4edcd62c068588f4d900199a18 +2
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 16 Sep 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq 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

Upgrade to a fixed release listed under Affected software.

Affected software

ProductAffectedFixed in
LinuxLinuxAffected
  • ≥ 7919d0a27f1e7cb324e023776aa1cbff00f1ee7b, < cd489b03587378645fe0d20142a33f1ed60bac98
Fixed in
  • cd489b03587378645fe0d20142a33f1ed60bac98
LinuxLinuxAffected
  • ≥ 7919d0a27f1e7cb324e023776aa1cbff00f1ee7b, < 9026932ac8be4d0ae01db47f23619a98cc57b671
Fixed in
  • 9026932ac8be4d0ae01db47f23619a98cc57b671
LinuxLinuxAffected
  • ≥ 7919d0a27f1e7cb324e023776aa1cbff00f1ee7b, < 7081224a59a0ca4edcd62c068588f4d900199a18
Fixed in
  • 7081224a59a0ca4edcd62c068588f4d900199a18
LinuxLinuxAffected
  • ≥ 7919d0a27f1e7cb324e023776aa1cbff00f1ee7b, < 6fedb2eaff77554ca7a0deffd2e8bc0d6e8b38b0
Fixed in
  • 6fedb2eaff77554ca7a0deffd2e8bc0d6e8b38b0
LinuxLinuxAffected
  • ≥ 7919d0a27f1e7cb324e023776aa1cbff00f1ee7b, < 0d53a47c913d0bce3b5ec35c28cbcca4d015f33d
Fixed in
  • 0d53a47c913d0bce3b5ec35c28cbcca4d015f33d
LinuxLinuxAffected
  • =4.9
Fixed in–

AI-suggested

A fix is available and has been applied in specific Linux kernel commits identified by their hashes. Users should update to a Linux kernel version that includes these fixes to remediate the vulnerability. No additional mitigation actions are indicated beyond applying the official patch.

Description

CVE-2026-90036 is a critical use-after-free vulnerability in the Linux kernel's NFSD component related to client handling during blocked-lock reaping. The flaw arises when a client reference is dropped prematurely, allowing a concurrent operation to free the client while it is still being accessed, leading to a use-after-free condition. This vulnerability has been fixed in specific Linux kernel commits.

References

Community reviews

Loading reviews…