CVE-2026-97925

A flaw was found in the Linux kernel's timer tick broadcast subsystem. A race condition occurs when installing a replacement clock event device concurrently with ongoing tick broadcast operations, causing the system to attempt to arm a detached timer device. If the central processing unit (CPU) associated with the original device is subsequently taken offline, this condition triggers a kernel crash, allowing a local user to cause a Denial of Service (DoS).

A MODERATE severity race condition flaw was found in the Linux kernel's timer tick broadcast subsystem. tick_install_broadcast_device() is not serialized against concurrent tick broadcast operations, so when a replacement clock event device is installed while another CPU is performing broadcast handling, the broadcast code can arm a device that has already been shut down and detached. If the original broadcast device has a restricted interrupt affinity mask and the last CPU in that mask is subsequently taken offline, the BUG() in tick_cleanup_dead_cpu() triggers and causes a kernel crash. A local user able to trigger clock event device replacement and CPU hotplug operations could use this race to cause a denial of service; the flaw affects only system availability and does not impact confidentiality or integrity. Red Hat Enterprise Linux 6 is not affected because the vulnerable code is not present in that stream. The fix is deferred for the affected Red Hat Enterprise Linux, Red Hat In-Vehicle OS, and OpenShift Container Platform streams; until a fix is delivered, the residual risk is a local, hard-to-trigger kernel crash (denial of service) on affected systems.

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 for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.