Race condition in Linux kernel - CVE-2026-89517
Published: September 12, 2026
Vulnerability identifier: #VU149285
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-89517
CWE-ID: CWE-362
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a race condition in the sched_ext core scheduling task-selection logic when task selections interleave after dispatch releases the runqueue lock. A local user can trigger a cookied ping-pong workload to cause a denial of service.
Exploitation requires core scheduling on an SMT system.
Affected software
Linux kernel
How to mitigate CVE-2026-89517
Install security update from vendor's repository.