NULL Pointer Dereference Affecting kernel-modules-core package, versions *


Severity

Recommended
0.0
medium
0
10

Based on CentOS security rating.

Threat Intelligence

EPSS
0.17% (6th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-CENTOS10-KERNELMODULESCORE-21740843
  • published27 Oct 2026
  • disclosed23 Oct 2026

Introduced: 23 Oct 2026

NewCVE-2026-99065  (opens in a new tab)
CWE-476  (opens in a new tab)

How to fix?

There is no fixed version for Centos:10 kernel-modules-core.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-modules-core package and not the kernel-modules-core package as distributed by Centos. See How to fix? for Centos:10 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

cgroup/cpuset: Handle cpu hotplug race in guarantee_active_cpus()

With commit 2125c0034c5d ("cgroup/cpuset: Make cpuset hotplug processing synchronous"), the cpuset hotplug operation becomes synchronous. That commit also removes the code that handles race between cpuset_hotplug_work and cpu hotplug notifier with the assumption that race is now gone. Later commit 7a0aabd9ce69 ("cgroup/cpuset: Always use cpu_active_mask") updates the cpuset code to always use cpu_active_mask instead of cpu_online_mask in some places including guarantee_online_cpus() which is renamed to guarantee_active_cpus() in that commit.

In the case of CPU offline operation, cpu_active_mask is updated first in sched_cpu_deactivate() to remove the offline CPU before cpuset_handle_hotplug() is called to update the effective_cpus of the affected cpusets. The cpu_online_mask is updated after that near the end of the offline operation to remove the offline CPU. As a result, the race comes back and the top cpuset may not have any active CPU leading to NULL pointer dereference during the race window when guarantee_active_cpus() is called after cpu_active_mask is updated to remove the CPU to be torn down but before cpuset_handle_hotplug() is able to properly update the effective_cpus of the top cpuset.

Fix this by adding back the NULL cs check to avoid this problem.

CVSS Base Scores

version 3.1