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. This flaw can grant a local attacker kernel‑level privilege escalation if successfully triggered.

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.

The EPSS Score is less than 1%, indicating a low probability of exploitation, but the vulnerability is high severity with a CVSS score of 7.8. 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 remains 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. Evaluate current kernel versions for the presence of the specific commit identifiers referenced in the advisory and apply an update as soon as possible.