Impact
The vulnerability is a use‑after‑free in the ALSA PCM unlink path. When a linked stream is drained, an on‑stack wait entry is attached to the peer's sleep structure and later removed only if that peer remains in the same group. If the group membership changes before the wait ends, the entry can remain on a freed stack frame and a subsequent wake‑up will walk this stale reference, potentially causing a kernel crash or an opportunity for arbitrary code execution. The flaw is classified as CWE‑416 and can grant a local attacker kernel‑level privilege escalation if successfully triggered.
Affected Systems
It affects the Linux kernel across all releases that contain the ALSA PCM unlink code until the fix is applied. Vendors identified are the Linux kernel maintainer, and all distributions using the stock kernel are potentially impacted. The vulnerability is present in the mainline kernel source and any derivative that has not been patched to include the commit that removes the conditional wait removal.
Risk and Exploitability
The exact CVSS score is not listed, and EPSS data is unavailable, but the nature of the bug – a use‑after‑free in kernel code – typically places it in high to critical severity. There is no known public exploit and the vulnerability is not listed in CISA KEV, so the likelihood of immediate exploitation is uncertain. Nonetheless, because the flaw can be reached by unlinking a stream that is draining or draining, any system that performs such operations is at risk until the kernel is updated. Recommend evaluating current kernel versions for the presence of the specific commit identifiers referenced in the advisory and applying an update as soon as possible.
OpenCVE Enrichment