Medium 5.5Published Apr 16, 2025

CVE-2025-23131dlm: prevent NPD when writing a positive value to event_done

Updated under an hour ago (Oct 28, 2026, 2:40 AM ET)

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It affects Linux and 2 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: dlm: prevent NPD when writing a positive value to event_done do_uevent returns the value written to event_done. In case it is a positive value, new_lockspace would undo all the work, and lockspace would not be set. __dlm_new_lockspace, however, would treat that positive value as a success due to commit 8511a2728ab8 ("dlm: fix use count with multiple joins"). Down the line, device_create_lockspace would pass that NULL lockspace to dlm_find_lockspace_local, leading to a NULL pointer dereference. Treating such positive values as successes prevents the problem. Given this has been broken for so long, this is unlikely to break userspace expectations.

CVSS: 5.5 MEDIUM (v3.1, NVD)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Modified
Record last updated: Oct 14, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from 8511a2728ab82cab398e39d019f5cf1246021c1c before a1c41aebb184d9228a440dcb6761224e65b0e49a; from 8511a2728ab82cab398e39d019f5cf1246021c1c before ee28d99d789b077565cbe0377374d1e826c64d93; from 8511a2728ab82cab398e39d019f5cf1246021c1c before c7837e2c96559663c33f43da403d9cf3cf77cfa7; 8511a2728ab82cab398e39d019f5cf1246021c1c builds before 7109d69bec6edce546dc870e66bd2b668a3d5549; 8511a2728ab82cab398e39d019f5cf1246021c1c builds before 10b7a59814765d18d43555c9cef4eb3048b7e8a3; from 8511a2728ab82cab398e39d019f5cf1246021c1c before b73c4ad4d387fe5bc988145bd9f1bc0de76afd5c; 8511a2728ab82cab398e39d019f5cf1246021c1c builds before 8e2bad543eca5c25cd02cbc63d72557934d45f13	CNA record
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem siemens:simatic_s7_1500_tm_mfp_gnu_linux_subsystem (from the name)	all versions	CISA ADP
linux linux_kernel linux:linux_kernel	from 2.6.31 before 6.14.2	NVD

References

References

https://git.kernel.org/stable/c/a1c41aebb184d9228a440dcb6761224e65b0e49a
https://git.kernel.org/stable/c/ee28d99d789b077565cbe0377374d1e826c64d93
https://git.kernel.org/stable/c/c7837e2c96559663c33f43da403d9cf3cf77cfa7
https://git.kernel.org/stable/c/7109d69bec6edce546dc870e66bd2b668a3d5549
https://git.kernel.org/stable/c/10b7a59814765d18d43555c9cef4eb3048b7e8a3
https://git.kernel.org/stable/c/b73c4ad4d387fe5bc988145bd9f1bc0de76afd5c	patch
https://git.kernel.org/stable/c/8e2bad543eca5c25cd02cbc63d72557934d45f13	patch
https://cert-portal.siemens.com/productcert/html/ssa-784472.html

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.