# CVE-2026-64490: ALSA: virtio: Validate control metadata from the device

> A malicious or buggy virtio-sound device can trigger out-of-bounds memory access in the Linux kernel, potentially leading to code execution or system crashes.

- **Severity:** High 8.4 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Jul 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-64490, DEBIAN-CVE-2026-64490, GHSA-4qj6-j88p-jqg9, ROOT-OS-UBUNTU-2204-CVE-2026-64490, UBUNTU-CVE-2026-64490

## What is CVE-2026-64490?

CVE-2026-64490 is a high-severity memory corruption vulnerability in Linux, published on 25 Jul 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: virtio: Validate control metadata from the device

virtio-snd control handling trusts the device-provided control type and
value count returned by the device.

That metadata is then used directly to index g_v2a_type_map[] in
virtsnd_kctl_info(), and to size loops and memcpy() operations in
virtsnd_kctl_get() and virtsnd_kctl_put() against fixed-size
virtio_snd_ctl_value and snd_ctl_elem_value arrays.

A buggy or malicious device can therefore trigger out-of-bounds access by
advertising an invalid control type or an oversized value count.

Validate control type and count once in virtsnd_kctl_parse_cfg(), before
querying enumerated items or exposing the control to ALSA.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-64490?


## How do I fix CVE-2026-64490?

Apply the vendor's patch.

## Is CVE-2026-64490 being exploited?

There is no known exploitation of CVE-2026-64490 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64490 and fix it if it is affected.

What it is: CVE-2026-64490 is a high-severity memory corruption vulnerability in Linux, published on 25 Jul 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-2026-64490 in the wild and no public exploit code.

Affected product: Linux. 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-2026-64490/ (Markdown: https://insights.sbomify.com/CVE-2026-64490/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64490
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64490
- OSV: https://osv.dev/vulnerability/CVE-2026-64490

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64490/
Summaries are generated and may contain mistakes; the official description above is the record.