# CVE-2026-53242: ALSA: PCM: Fix wait queue list corruption in snd_pcm_drain() on linked streams

> A race condition in the Linux kernel ALSA PCM driver causes list corruption and kernel panic during stream draining, leading to denial of service.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **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:** Yes
- **Published:** 25 Jun 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-90866, BELL-CVE-2026-53242, DEBIAN-CVE-2026-53242, GHSA-2p59-xc6p-6w7c, ROOT-OS-DEBIAN-11-CVE-2026-53242, ROOT-OS-DEBIAN-12-CVE-2026-53242, ROOT-OS-UBUNTU-2404-CVE-2026-53242, UBUNTU-CVE-2026-53242

## What is CVE-2026-53242?

CVE-2026-53242 is a high-severity vulnerability in Linux kernel, published on 25 Jun 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: Fix wait queue list corruption in snd_pcm_drain() on linked streams

snd_pcm_drain() uses init_waitqueue_entry which does not clear
entry.prev/next, and add_wait_queue with a conditional
remove_wait_queue that is skipped when to_check is no longer
in the group after concurrent UNLINK.  The orphaned wait entry
remains on the unlinked substream sleep queue.  On the next
drain iteration, add_wait_queue adds the entry to a new queue
while still linked on the old one, corrupting both lists.  A
subsequent wake_up dereferences NULL at the func pointer
(mapped from the spinlock at offset 0 of the misinterpreted
wait_queue_head_t), causing a kernel panic.

Replace init_waitqueue_entry/add_wait_queue/conditional
remove_wait_queue with init_wait_entry/prepare_to_wait/
finish_wait.  init_wait_entry clears prev/next via
INIT_LIST_HEAD on each iteration and sets
autoremove_wake_function which auto-removes the entry on
wake-up.  finish_wait safely handles both the already-removed
and still-queued cases.

Weakness: CWE-476 (NULL Pointer Dereference), CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2026-53242?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-53242?

Apply the vendor's patch.

## Is CVE-2026-53242 being exploited?

There is no known exploitation of CVE-2026-53242 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-53242 and fix it if it is affected.

What it is: CVE-2026-53242 is a high-severity vulnerability in Linux kernel, published on 25 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-53242 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-53242/ (Markdown: https://insights.sbomify.com/CVE-2026-53242/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53242
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53242
- OSV: https://osv.dev/vulnerability/CVE-2026-53242

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53242/
Summaries are generated and may contain mistakes; the official description above is the record.