CVE-2026-97961

A flaw was found in the Linux kernel's perf subsystem, which can lead to a Denial of Service (DoS). A local user can trigger this issue by manipulating performance monitoring event limits through I/O control (ioctl) requests. When the event limit expires, the kernel improperly removes an entry from an internal callback list while actively iterating over it, causing list corruption and crashing the system.

A moderate severity denial of service flaw was found in the Linux kernel's performance monitoring (perf) subsystem. When a local user arms a perf event with a limit via the PERF_EVENT_IOC_REFRESH ioctl and that event limit reaches zero, perf_event_overflow() can call perf_sched_cb_dec(), which removes an entry from the internal sched_cb_list callback list while perf_pmu_sched_task() is still iterating over that list. Continuing to traverse the corrupted list causes a kernel crash. Red Hat rates this flaw as Moderate (CVSS 3.1 base score 5.5, CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H), reflecting a local, authenticated denial of service with no impact on confidentiality or integrity. The kernel in Red Hat Enterprise Linux 9 and 10, Red Hat In-Vehicle OS 2, and OpenShift Container Platform 4.16 and later (RHEL CoreOS 9 based), as well as OpenShift 5.x, is affected. Red Hat Enterprise Linux 6, 7, 8, and 9.2 releases and OpenShift Container Platform 4.12-4.15 are not affected because the vulnerable code is not present in those kernels. For the affected products the fix is deferred to a future planned update; the residual risk is limited to a local user who can open perf events reliably crashing the system, with no privilege escalation or information disclosure involved.

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.