CVE-2026-80716 ALSA: pcm: wake linked drain waiters on unlink
A use-after-free in the Linux kernel ALSA PCM subsystem allows local attackers to execute arbitrary code or escalate privileges via race conditions during stream unlinking.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-80716?
CVE-2026-80716 is a high-severity use after free vulnerability in Linux, published on 28 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
ALSA: pcm: wake linked drain waiters on unlink
snd_pcm_drain() on a linked stream parks an on-stack wait entry on the drained peer's runtime->sleep, and after schedule_timeout() removes it only if that peer is still found in the caller's group. If group membership changes during the wait and the sleep ends by signal or timeout (so autoremove_wake_function() does not run), finish_wait() is skipped and snd_pcm_drain() returns with the entry still queued on that stream's sleep list; a later wake_up() then walks a freed stack frame. This is reachable by unlinking either the drained or the draining stream.
Unlike the close path (snd_pcm_drop() -> snd_pcm_post_stop()), snd_pcm_unlink() never wakes the sleep queues. Wake every group member under the group lock before the membership change, so a linked drainer is released and drops its entry while the streams are still grouped.
The window was opened when snd_pcm_link_rwsem stopped being held across the wait and the removal became conditional on group membership (see Fixes). The later switch to finish_wait() kept that conditional removal, so the signal/timeout case remained.
Which versions are affected by CVE-2026-80716?
How do I fix CVE-2026-80716?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-80716 being exploited?
There is no known exploitation of CVE-2026-80716 in the wild and no public exploit code.
Sources
Also known as AZL-98171, BELL-CVE-2026-80716, DEBIAN-CVE-2026-80716, GHSA-j63j-489f-v3q9, UBUNTU-CVE-2026-80716.