CVE-2025-38338: Linux kernel · fs/nfs/read: fix double-unlock bug in nfs_return_empty_folio()
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in 14f5549ad163be2c018abc1bb38370fff617a243 : patch Linux kernel soon.
Data as of 5 Nov 2026, 21:33 UTC
Rated High by Threat Radar's AI analysis · No CVSS score from NVD or the CNA
Thin evidence
One scorer or none- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-11-05.
- Patch
- Available – fixed in 14f5549ad163be2c018abc1bb38370fff617a243, 5bf0b9eeb0174686f22c2e5b8fb9f47ad25da6f5, 4c10fa44bc5f700e2ea21de2fbae520ba21f19d9 +1
Exploitation evidence
Disclosed: evidence found.
CVE published 10 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 5 Nov 2026.
What to do
Upgrade Linux kernel to 14f5549ad163be2c018abc1bb38370fff617a243, 5bf0b9eeb0174686f22c2e5b8fb9f47ad25da6f5, 4c10fa44bc5f700e2ea21de2fbae520ba21f19d9 or 1e93b61d3eaa14bfebcc2716ac09d43f3845d420.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix for this vulnerability is available and has been applied in the Linux kernel. Users should update to the fixed versions identified by the provided commit hashes. No additional mitigation is required once the kernel is updated.
Description
A double-unlock bug in the Linux kernel's NFS read path (nfs_return_empty_folio) could cause deadlocks when a file is read concurrently with truncation by another NFS client. This occurs because folio_unlock() is called twice without a necessary check, leading to inconsistent folio lock state and potentially causing processes to hang indefinitely.
References
- git.kernel.org/stable/c/14f5549ad163be2c018abc1bb38370fff617a243 (opens in a new tab)
- git.kernel.org/stable/c/5bf0b9eeb0174686f22c2e5b8fb9f47ad25da6f5 (opens in a new tab)
- git.kernel.org/stable/c/1e93b61d3eaa14bfebcc2716ac09d43f3845d420 (opens in a new tab)
- git.kernel.org/stable/c/4c10fa44bc5f700e2ea21de2fbae520ba21f19d9 (opens in a new tab)