# CVE-2026-89976: accel/ethosu: fix job completion fence cleanup

> A memory corruption vulnerability in the Linux kernel Ethos-U driver allows local attackers to cause denial of service or potentially execute code via improper fence cleanup.

- **Severity:** Not scored
- **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:** 16 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-89976, GHSA-xw3m-mp44-62gr, UBUNTU-CVE-2026-89976

## What is CVE-2026-89976?

CVE-2026-89976 is a memory corruption vulnerability in Linux, published on 16 Sep 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:

accel/ethosu: fix job completion fence cleanup

ethosu_ioctl_submit_job() allocates done_fence before validating buffer
handles. Errors after allocation call ethosu_job_err_cleanup(), which frees
the job but leaks the uninitialized fence.

A scheduler dependency error also lets ethosu_job_run() return before
dma_fence_init(). Normal cleanup then passes a zeroed refcount to
dma_fence_put().

Release done_fence in the common cleanup path and use
dma_fence_was_initialized() to distinguish initialized fences from raw
allocations.

[robh: also fix goto]

## Which versions are affected by CVE-2026-89976?


## How do I fix CVE-2026-89976?

Apply the vendor's patch.

## Is CVE-2026-89976 being exploited?

There is no known exploitation of CVE-2026-89976 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-89976 and fix it if it is affected.

What it is: CVE-2026-89976 is a memory corruption vulnerability in Linux, published on 16 Sep 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-2026-89976 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-2026-89976/ (Markdown: https://insights.sbomify.com/CVE-2026-89976/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-89976
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-89976
- OSV: https://osv.dev/vulnerability/CVE-2026-89976

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-89976/
Summaries are generated and may contain mistakes; the official description above is the record.