CVE-2026-99065
kernel: cgroup/cpuset: Handle cpu hotplug race in guarantee_active_cpus()
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 cpuset subsystem. A race condition during CPU hotplug offline operations can leave the root control group with no active processors before CPU masks are updated, resulting in a null pointer dereference. A privileged local user or process initiating CPU offlining could trigger this flaw to crash the system, leading to 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-476 · NULL Pointer Dereference