CVE-2026-90234: Linux kernel · NFS: Return a delegation the client fails to record
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.5 High · fixed in fe3b1c8966a27b70599d28ce7e80819adac1ff22 : patch Linux kernel soon.
Data as of 26 Oct 2026, 20:01 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 49% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in fe3b1c8966a27b70599d28ce7e80819adac1ff22, 92533e49fe3c455088657b862cf3562260c0ce25, 6822ba1ae9b6df6a094f7f8998f1da734c85fa19 +2
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
AI-suggested
This vulnerability has been fixed in the Linux kernel as indicated by multiple fixed commits. Users should update their Linux kernel to a version including these fixes. No additional mitigations or workarounds are specified or required.
Description
CVE-2026-90234 is a high-severity vulnerability in the Linux kernel's NFS client implementation where certain error flows fail to send DELEGRETURN when relinquishing delegations. This causes the server to incorrectly believe the client still holds the delegation, leading to state inconsistencies and indefinite recall loops. The issue has been fixed in specific Linux kernel commits.
References
- git.kernel.org/stable/c/9e71e332fa2c7a48f3d00001f856a13cc2d69639 (opens in a new tab)
- git.kernel.org/stable/c/fe3b1c8966a27b70599d28ce7e80819adac1ff22 (opens in a new tab)
- git.kernel.org/stable/c/6822ba1ae9b6df6a094f7f8998f1da734c85fa19 (opens in a new tab)
- git.kernel.org/stable/c/92533e49fe3c455088657b862cf3562260c0ce25 (opens in a new tab)
- git.kernel.org/stable/c/220af23d863995091f0edeb1e6aa0945b3db8b37 (opens in a new tab)