# CVE-2026-80539: drm/amdgpu: disallow multiple FENCE chunks in one submit

> A local attacker can leak memory references in the AMDGPU driver by submitting duplicate fence chunks, leading to resource exhaustion and denial of service.

- **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:** 26 Aug 2026
- **Updated:** 27 Aug 2026
- **Also known as:** AZL-97749, BELL-CVE-2026-80539, DEBIAN-CVE-2026-80539, GHSA-5jg9-2pjg-5862, UBUNTU-CVE-2026-80539

## What is CVE-2026-80539?

CVE-2026-80539 is a 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:

drm/amdgpu: disallow multiple FENCE chunks in one submit

amdgpu_cs_pass1() dispatches on chunk_id once per chunk without
rejecting repeated ids. p->uf_bo is a single-slot field, so a
submission carrying two AMDGPU_CHUNK_ID_FENCE chunks runs
amdgpu_cs_p1_user_fence() twice, and the second run overwrites
p->uf_bo with a freshly referenced BO without dropping the reference
taken by the first.

amdgpu_cs_parser_fini() only unrefs the final p->uf_bo, so every FENCE
chunk but the last leaks a BO reference. The leaked BO outlives handle
close and process exit.

Reject duplicate FENCE chunks the same way commit fec5f8e8c6bc
("drm/amdgpu: disallow multiple BO_HANDLES chunks in one submit") did
for p->bo_list.

(cherry picked from commit 665b1fc2a1845206408f9a2c6da67101789edb82)

## Which versions are affected by CVE-2026-80539?


## How do I fix CVE-2026-80539?

Apply the vendor's patch.

## Is CVE-2026-80539 being exploited?

There is no known exploitation of CVE-2026-80539 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80539 and fix it if it is affected.

What it is: CVE-2026-80539 is a 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-2026-80539 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-2026-80539/ (Markdown: https://insights.sbomify.com/CVE-2026-80539/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80539
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80539
- OSV: https://osv.dev/vulnerability/CVE-2026-80539

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80539/
Summaries are generated and may contain mistakes; the official description above is the record.