# CVE-2026-74418: dma-fence: Fix potential tracepoint null pointer dereferences

> A null pointer dereference in Linux kernel DMA fence tracepoints can cause a system crash, requiring local access to exploit.

- **Severity:** Not scored
- **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:** 15 Aug 2026
- **Updated:** 17 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-74418, GHSA-34jm-85m6-f5hv, UBUNTU-CVE-2026-74418

## What is CVE-2026-74418?

CVE-2026-74418 is a 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: Fix potential tracepoint null pointer dereferences

Trace_dma_fence_signaled, trace_dma_fence_wait_end and
trace_dma_fence_destroy can all currently dereference a null fence->ops
pointer after it has been reset on fence signalling.

Lets use the safe string getters for most tracepoints to avoid this class
of a problem, while for the signal tracepoint we move it to before ops are
cleared to avoid losing the driver and timeline name information. Apart
from moving it we also need to add a new tracepoint class to bypass the
safe name getters since the signaled bit is already set.

For dma_fence_init we also need to use the new tracepoint class since the
rcu read lock is not held there, and we can do the same for the enable
signaling since there we are certain the fence cannot be signaled while
we are holding the lock and have even validated the fence->ops.

## Which versions are affected by CVE-2026-74418?


## How do I fix CVE-2026-74418?

Apply the vendor's patch.

## Is CVE-2026-74418 being exploited?

There is no known exploitation of CVE-2026-74418 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74418 and fix it if it is affected.

What it is: CVE-2026-74418 is a 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-2026-74418 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-2026-74418/ (Markdown: https://insights.sbomify.com/CVE-2026-74418/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74418
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74418
- OSV: https://osv.dev/vulnerability/CVE-2026-74418

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74418/
Summaries are generated and may contain mistakes; the official description above is the record.