CVE-2025-40087: Linux kernel · NFSD: Define a proc_layoutcommit for the FlexFiles layout type
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.5 High · fixed in 5.15.0-1100.107~20.04.2 : patch Linux kernel soon.
Data as of 28 Oct 2026, 11:18 UTC
- Patch
- Available – fixed in 5.15.0-1100.107~20.04.2, 5.15.0-1110.119~20.04.1, 5.15.0-1100.109~20.04.1 +71
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 30 Oct 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-8029-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8030-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8034-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8034-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8048-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-6 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linuxpkg:deb/ubuntu/linux?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle?arch=source&distro=questingOther 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 patch is available and included in Linux kernel versions 5.15.0-1094.97~20.04.1 and later. Users and administrators should update to these fixed kernel versions or later to remediate this vulnerability. The Ubuntu security advisory USN-8029-1 provides official updates addressing this and other kernel issues.
Description
CVE-2025-40087 is a vulnerability in the Linux kernel's NFSD subsystem related to the FlexFiles layout type. It addresses a crash that could occur if a pNFS client sends a LAYOUTCOMMIT operation on a FlexFiles layout. The issue has been fixed in multiple Linux kernel versions starting from 5.15.0-1094.97~20.04.1 and later. The vulnerability has a high severity score and does not involve confidentiality or integrity impacts but can cause denial of service via a crash.
References
- ubuntu.com/security/CVE-2025-40087 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-40087 (opens in a new tab)
- git.kernel.org/linus/4b47a8601b71ad98833b447d465592d847b4dc77 (opens in a new tab)
- git.kernel.org/stable/c/34d187e020cbda112a6c6f094f0ca5e6a8672b75 (opens in a new tab)
- git.kernel.org/stable/c/4b47a8601b71ad98833b447d465592d847b4dc77 (opens in a new tab)
- git.kernel.org/stable/c/785ec512afa80d0540f2ca797c0e56de747a6083 (opens in a new tab)
- git.kernel.org/stable/c/a156af6a4dc38c2aa7c98e89520a70fb3b3e7df4 (opens in a new tab)
- git.kernel.org/stable/c/a75994dd879401c3e24ff51c2536559f1a53ea27 (opens in a new tab)
- git.kernel.org/stable/c/ba88a53d7f5df4191583abf214214efe0cda91d2 (opens in a new tab)
- git.kernel.org/stable/c/da9129ef77786839a3ccd1d7afeeab790bceaa1d (opens in a new tab)
- git.kernel.org/stable/c/f7353208c91ab004e0179c5fb6c365b0f132f9f0 (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8030-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8034-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-5 (opens in a new tab)