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

What is CVE-2025-23131?

CVE-2025-23131 is a medium-severity vulnerability in Linux kernel, published on 16 Apr 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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.

Weakness: CWE-476

Which versions are affected by CVE-2025-23131?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2025-23131?

Apply the vendor's patch.

Is CVE-2025-23131 being exploited?

There is no known exploitation of CVE-2025-23131 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-62788, AZL-69653, BELL-CVE-2025-23131, DEBIAN-CVE-2025-23131, GHSA-3299-q63p-824w, ROOT-OS-DEBIAN-11-CVE-2025-23131 and 5 more.