CVE-2026-80716

Received Received - Intake

Linux Kernel PCM Subsystem Use-After-Free Vulnerability

Publication date: 2026-08-28

Last updated on: 2026-08-29

Assigner: kernel.org

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.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published

2026-08-28

Last Modified

2026-08-29

Generated

2026-09-17

AI Q&A

2026-08-28

EPSS Evaluated

2026-09-15

NVD

CVE-2026-80716

EUVD

EUVD-2026-67451

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability in the Linux kernel involves a race condition in the ALSA PCM (sound) subsystem. When snd_pcm_drain() is called on a linked audio stream, it may leave a wait entry on the sleep list of another stream if group membership changes during a wait. This can lead to a use-after-free scenario when a later wake_up() tries to access a freed stack frame.

Detection Guidance

This vulnerability is specific to the Linux kernel's ALSA PCM subsystem and does not have a direct network detection method. Detection requires checking kernel versions and examining system logs for related crashes or memory corruption issues. Use commands like 'uname -a' to check kernel version and 'dmesg' or 'journalctl -k' to look for kernel errors or warnings.

Impact Analysis

This vulnerability could cause system instability, crashes, or potential privilege escalation if exploited. It primarily affects systems using ALSA for audio processing, potentially leading to denial-of-service conditions or unexpected behavior in audio applications.

Compliance Impact

This vulnerability does not directly affect compliance with GDPR, HIPAA, or similar standards. It is a low-level Linux kernel issue related to audio stream handling that could lead to memory corruption or crashes. Compliance impacts would only occur if exploitation disrupted system integrity or data processing, which is not described in the provided context.

Mitigation Strategies

Apply the latest kernel updates from your Linux distribution to ensure the vulnerability is patched. If immediate patching is not possible, avoid using ALSA PCM linked streams or unlinking streams during active operations to reduce exposure. Monitor kernel logs for crashes or memory corruption as potential indicators of exploitation.

Hi! I’m here to help you understand CVE-2026-80716. Ask me anything about the vulnerability, its impact, or mitigation strategies.

0/70