SB2026032083 - Race condition in Linux kernel events

Description

This security bulletin contains information about 1 security vulnerability.

1) Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') (CVE-ID: CVE-2026-23271)

The vulnerability allows a local user to execute arbitrary code, escalate privileges, and cause a denial of service.

The vulnerability exists due to a race condition in the perf subsystem when handling performance events. A local user can trigger a use-after-free condition during event overflow processing to execute arbitrary code, escalate privileges, and cause a denial of service.

The issue arises from improper synchronization between __perf_event_overflow() and perf_remove_from_context(), where the overflow handler may access memory after it has been freed by context removal routines. The attacker must be able to create and manipulate perf events, which typically requires low-privileged user access to the perf subsystem.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/3f89b61dd504c5b6711de9759e053b082f9abf12
• https://git.kernel.org/stable/c/5c48fdc4b4623533d86e279f51531a7ba212eb87
• https://git.kernel.org/stable/c/bb190628fe5f2a73ba762a9972ba16c5e895f73e
• https://git.kernel.org/stable/c/c9bc1753b3cc41d0e01fbca7f035258b5f4db0ae