# CVE-2026-80572: Input: byd - synchronize timer deletion before freeing private data

> A race condition in the Linux kernel BYD input driver allows 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:** 26 Aug 2026
- **Updated:** 16 Oct 2026
- **Also known as:** AZL-97769, BELL-CVE-2026-80572, DEBIAN-CVE-2026-80572, GHSA-g6j6-j6hv-j2v2, UBUNTU-CVE-2026-80572

## What is CVE-2026-80572?

CVE-2026-80572 is a high-severity use after free vulnerability in Linux, published on 26 Aug 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:

Input: byd - synchronize timer deletion before freeing private data

byd_disconnect() uses timer_delete() before freeing the driver's private
data.  This does not wait for a running byd_clear_touch() callback, which
dereferences the private data and its psmouse pointer.  A callback racing
with disconnect can therefore access the private data after it has been
freed.  The timer can also still be re-armed by byd_process_byte() while
the disconnect is in progress.

Use timer_shutdown_sync() before freeing the private data: it waits for
a running callback and turns any later re-arm attempt into a no-op.

## Which versions are affected by CVE-2026-80572?


## How do I fix CVE-2026-80572?

Apply the vendor's patch.

## Is CVE-2026-80572 being exploited?

There is no known exploitation of CVE-2026-80572 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80572 and fix it if it is affected.

What it is: CVE-2026-80572 is a high-severity use after free vulnerability in Linux, published on 26 Aug 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-2026-80572 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-2026-80572/ (Markdown: https://insights.sbomify.com/CVE-2026-80572/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80572
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80572
- OSV: https://osv.dev/vulnerability/CVE-2026-80572

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80572/
Summaries are generated and may contain mistakes; the official description above is the record.