Use-after-free in Linux kernel - CVE-2026-99204

Vulnerability details

The vulnerability allows a local privileged user to potentially cause a denial of service through invalid kernel memory access.

The vulnerability exists due to use-after-free in the Linux kernel OCFS2 DLM debug_state_print() function when reading recovery participant records without holding the lock that protects their list. A local privileged user can open the DLM debugfs state interface concurrently with recovery-area teardown to trigger reads of freed participant records, potentially causing a kernel crash.

Affected software

How to mitigate CVE-2026-99204

External References

• https://git.kernel.org/stable/c/04d4571c00db61a9664f387752fa05cb3c08a537
• https://git.kernel.org/stable/c/2bc426a32bfb78868c7f76d9547132837b6b5284
• https://git.kernel.org/stable/c/4c435828932bf46f29860e4a0375bcae101b778a

Related Security Bulletins

• Use-after-free in Linux kernel ocfs2 dlm
• Debian update for linux