# CVE-2026-80574: Input: focaltech - fix array out-of-bounds in focaltech_process_rel_packet

> An out-of-bounds write in the Focaltech input driver allows attackers to corrupt memory, potentially leading to code execution or privilege escalation.

- **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:** 26 Aug 2026
- **Updated:** 16 Oct 2026
- **Also known as:** AZL-97839, BELL-CVE-2026-80574, DEBIAN-CVE-2026-80574, GHSA-qm8h-24xg-3v98, UBUNTU-CVE-2026-80574

## What is CVE-2026-80574?

CVE-2026-80574 is a high-severity memory corruption 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: focaltech - fix array out-of-bounds in focaltech_process_rel_packet

Make finger2 (and also finger1) unsigned, so that if the finger index in
the packet is 0 then subtracting 1 creates an array index which overflows
above the existing check for FOC_MAX_FINGERS, as the existing comment says
it should, instead of writing to state->fingers[-1].

## Which versions are affected by CVE-2026-80574?


## How do I fix CVE-2026-80574?

Apply the vendor's patch.

## Is CVE-2026-80574 being exploited?

There is no known exploitation of CVE-2026-80574 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80574 and fix it if it is affected.

What it is: CVE-2026-80574 is a high-severity memory corruption 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-2026-80574 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-2026-80574/ (Markdown: https://insights.sbomify.com/CVE-2026-80574/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80574
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80574
- OSV: https://osv.dev/vulnerability/CVE-2026-80574

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80574/
Summaries are generated and may contain mistakes; the official description above is the record.