CVE-2026-99085
kernel: sched_ext: Fix CPU hotplug hang when a dying CPU's tasks sit in the BPF scheduler
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · October 23, 2026
Updated · October 27, 2026
Description
A flaw was found in the Linux kernel's extensible scheduler (sched_ext). When a central processing unit (CPU) is taken offline while tasks remain managed by the scheduler, the inactive CPU stops dispatching those tasks, preventing the shutdown thread from finishing. A local attacker could exploit this condition to cause the CPU offline operation to hang indefinitely, resulting in a Denial of Service (DoS).
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 4.1CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
CWE-833 · Deadlock