Race condition in Linux kernel - CVE-2026-99140

Vulnerability details

The vulnerability allows a local privileged user to trigger kernel warnings and cause incorrect timestamps in tracing histograms.

The vulnerability exists due to a race condition in hist_field_timestamp() in kernel/trace/trace_events_hist.c when a histogram trigger is attached while a filtered event is being processed in a per-CPU temporary buffer. A local privileged user can race histogram trigger registration against event processing to cause timestamp retrieval from an event without an active ring buffer commit, triggering a kernel warning and recording an incorrect timestamp.

Affected software

How to mitigate CVE-2026-99140

External References

• https://git.kernel.org/stable/c/09c7cce2e59e6b3b1807520bcb1980c561f15d1e
• https://git.kernel.org/stable/c/89e90b16aadd6e66bd0323bc8dfc76a62e756b57
• https://git.kernel.org/stable/c/9414ca3b99e5a7f1f3bf51c2a01b383e1b355dd0

Related Security Bulletins

• Race condition in Linux kernel trace
• Debian update for linux