# CVE-2026-64491: ALSA: usx2y: us144mkii: fix work UAF on disconnect

> A use-after-free vulnerability in the Linux kernel ALSA usx2y driver allows local attackers to execute arbitrary code or escalate privileges via device disconnection.

- **Severity:** Not scored
- **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:** 17 Aug 2026
- **Also known as:** BELL-CVE-2026-64491, DEBIAN-CVE-2026-64491, GHSA-97r3-fw5v-8xg8, ROOT-OS-UBUNTU-2204-CVE-2026-64491, UBUNTU-CVE-2026-64491

## What is CVE-2026-64491?

CVE-2026-64491 is an use after free 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: usx2y: us144mkii: fix work UAF on disconnect

tascam_disconnect() cancels capture_work and midi_in_work before
usb_kill_anchored_urbs() kills the capture/MIDI-in URBs.  Those URBs
self-resubmit, and their completion handlers reschedule the work.

A URB that completes in the small window between cancel_work_sync() and
usb_kill_anchored_urbs() therefore re-arms the work after its only
cancel.  Nothing cancels it again before snd_card_free() frees the
card-private tascam structure, so the work handler then runs on freed
memory.

Kill the anchored URBs before cancelling the work; once the work is
cancelled no remaining URB can complete to re-arm it.

## Which versions are affected by CVE-2026-64491?


## How do I fix CVE-2026-64491?

Apply the vendor's patch.

## Is CVE-2026-64491 being exploited?

There is no known exploitation of CVE-2026-64491 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64491 and fix it if it is affected.

What it is: CVE-2026-64491 is an use after free 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-2026-64491 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-2026-64491/ (Markdown: https://insights.sbomify.com/CVE-2026-64491/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64491
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64491
- OSV: https://osv.dev/vulnerability/CVE-2026-64491

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64491/
Summaries are generated and may contain mistakes; the official description above is the record.