CVE-2026-89580

A flaw was found in the Linux kernel's BPF (Berkeley Packet Filter) subsystem. A local attacker could exploit a timing issue in the __bpf_get_stack function. This occurs when a preemptible BPF program is scheduled out, allowing another task to overwrite a per-CPU buffer. This leads to an out-of-bounds write, potentially causing memory corruption.

This vulnerability is rated as Moderate impact because successful exploitation requires local access and precise timing to trigger a race condition in the kernel's stack unwinding helpers. An attacker must win a race during execution of a preemptible BPF tracing program on the same processor core to cause buffer corruption. Furthermore, loading and attaching tracing programs typically demands administrative privileges or relies on existing tracing sessions, significantly constraining an unprivileged attacker's ability to trigger the flaw reliably.

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.