# CVE-2026-46090: ALSA: aloop: Fix peer runtime UAF during format-change stop

> A race condition in the Linux kernel ALSA loopback driver allows a use-after-free, potentially enabling local attackers to execute code or escalate privileges.

- **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:** 27 May 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-88571, BELL-CVE-2026-46090, DEBIAN-CVE-2026-46090, GHSA-w9ff-9cjh-6463, ROOT-OS-DEBIAN-11-CVE-2026-46090, ROOT-OS-DEBIAN-12-CVE-2026-46090, ROOT-OS-UBUNTU-2204-CVE-2026-46090, ROOT-OS-UBUNTU-2404-CVE-2026-46090, UBUNTU-CVE-2026-46090

## What is CVE-2026-46090?

CVE-2026-46090 is a high-severity use after free vulnerability in Linux kernel, published on 27 May 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: aloop: Fix peer runtime UAF during format-change stop

loopback_check_format() may stop the capture side when playback starts
with parameters that no longer match a running capture stream. Commit
826af7fa62e3 ("ALSA: aloop: Fix racy access at PCM trigger") moved
the peer lookup under cable->lock, but the actual snd_pcm_stop() still
runs after dropping that lock.

A concurrent close can clear the capture entry from cable->streams[] and
detach or free its runtime while the playback trigger path still holds a
stale peer substream pointer.

Keep a per-cable count of in-flight peer stops before dropping
cable->lock, and make free_cable() wait for those stops before
detaching the runtime. This preserves the existing behavior while
making the peer runtime lifetime explicit.

Weakness: CWE-364 (Signal Handler Race Condition), CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-46090?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-46090?

Apply the vendor's patch.

## Is CVE-2026-46090 being exploited?

There is no known exploitation of CVE-2026-46090 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-2026-46090 and fix it if it is affected.

What it is: CVE-2026-46090 is a high-severity use after free vulnerability in Linux kernel, published on 27 May 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-2026-46090 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-2026-46090/ (Markdown: https://insights.sbomify.com/CVE-2026-46090/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-46090
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-46090
- OSV: https://osv.dev/vulnerability/CVE-2026-46090

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-46090/
Summaries are generated and may contain mistakes; the official description above is the record.