# CVE-2026-72095: dma-fence: Make dma_fence_dedup_array() robust against 0-count input

> A logic error in the Linux kernel's dma-fence deduplication function could lead to a null pointer dereference and system crash when processing zero-count inputs.

- **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:** 15 Aug 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-72095, DEBIAN-CVE-2026-72095, GHSA-cgwr-m873-g7w9, UBUNTU-CVE-2026-72095

## What is CVE-2026-72095?

CVE-2026-72095 is a high-severity vulnerability in Linux, published on 15 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:

dma-fence: Make dma_fence_dedup_array() robust against 0-count input

dma_fence_dedup_array() returns 1 when called with num_fences == 0:
the for-loop body never executes, j stays at 0, and the final
`return ++j` yields 1. This contradicts both the kernel-doc ("Return:
Number of unique fences remaining in the array") and the natural
expectation that 0 input gives 0 output.

The caller __dma_fence_unwrap_merge() bails out via the
`if (count == 0 || count == 1)` fast path and so is save.

But amdgpu_userq_wait_*() could reach the dedup call with a zero local
count and dereference an uninitialized fence slot in the array.

Make the contract match the documentation by returning 0 early. This
also skips an unnecessary sort() call on an empty array.

Weakness: CWE-170 (Improper Null Termination)

## Which versions are affected by CVE-2026-72095?


## How do I fix CVE-2026-72095?

Apply the vendor's patch.

## Is CVE-2026-72095 being exploited?

There is no known exploitation of CVE-2026-72095 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-72095 and fix it if it is affected.

What it is: CVE-2026-72095 is a high-severity vulnerability in Linux, published on 15 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-2026-72095 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-2026-72095/ (Markdown: https://insights.sbomify.com/CVE-2026-72095/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-72095
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-72095
- OSV: https://osv.dev/vulnerability/CVE-2026-72095

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-72095/
Summaries are generated and may contain mistakes; the official description above is the record.