CVE-2025-38393: Linux kernel · NFSv4/pNFS: Fix a race to wake on NFS_LAYOUT_DRAIN
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.5 High · fixed in 5.15.0-1092.99~20.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 34% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1092.99~20.04.1, 5.15.0-1096.105~20.04.1, 5.15.0-1092.101~20.04.1 +59
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 25 Jul 2025
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.
Patches and advisories
- ubuntu.com/security/notices/USN-7774-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7776-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-7833-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7834-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7833-2 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-aws-6.14pkg:deb/ubuntu/linux-aws-6.14?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: NFSv4/pNFS: Fix a race to wake on NFS_LAYOUT_DRAIN We found a few different systems hung up in writeback waiting on the same page lock, and one task waiting on the NFS_LAYOUT_DRAIN bit in pnfs_update_layout(), however the pnfs_layout_hdr's plh_outstanding count was zero. It seems most likely that this is another race between the waiter and waker similar to commit ed0172af5d6f ("SUNRPC: Fix a race to wake a sync task"). Fix it up by applying the advised barrier.
References
- ubuntu.com/security/CVE-2025-38393 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-38393 (opens in a new tab)
- git.kernel.org/linus/c01776287414ca43412d1319d2877cbad65444ac (opens in a new tab)
- git.kernel.org/stable/c/08287df60bac5b008b6bcdb03053988335d3d282 (opens in a new tab)
- git.kernel.org/stable/c/1f4da20080718f258e189a2c5f515385fa393da6 (opens in a new tab)
- git.kernel.org/stable/c/864a54c1243ed3ca60baa4bc492dede1361f4c83 (opens in a new tab)
- git.kernel.org/stable/c/8846fd02c98da8b79e6343a20e6071be6f372180 (opens in a new tab)
- git.kernel.org/stable/c/8ca65fa71024a1767a59ffbc6a6e2278af84735e (opens in a new tab)
- git.kernel.org/stable/c/c01776287414ca43412d1319d2877cbad65444ac (opens in a new tab)
- git.kernel.org/stable/c/e4b13885e7ef1e64e45268feef1e5f0707c47e72 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7776-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-7833-1 (opens in a new tab)