# CVE-2026-74381: gpu: host1x: Allow entries in BO caches to be freed

> A use-after-free vulnerability in the Linux kernel host1x GPU driver allows local attackers to cause denial of service or potentially execute code.

- **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:** BELL-CVE-2026-74381, DEBIAN-CVE-2026-74381, GHSA-v464-369q-ppmf, UBUNTU-CVE-2026-74381

## What is CVE-2026-74381?

CVE-2026-74381 is an use after free 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:

gpu: host1x: Allow entries in BO caches to be freed

When a buffer object is pinned via host1x_bo_pin() with a cache, the
resulting mapping is kept in the cache so it can be reused on subsequent
pins. Each mapping held a reference to the underlying host1x_bo (taken
in tegra_bo_pin / gather_bo_pin), so as long as a mapping was cached,
the bo itself could not be freed.

However, the only way to remove the cached mapping was through the free
path of the buffer object. This meant that if a bo got cached, it could
never get freed again.

Resolve the circularity by holding a weak reference to the bo from the
cache side. This is done by having the .pin callbacks not bump the bo's
refcount -- instead the common Host1x bo code does so, except for the
cache reference.

Also move the remove-cache-mapping-on-free code into a common function
inside Host1x code. This is only called from the TegraDRM GEM buffers
since those are the only ones that can be cached at the moment.

## Which versions are affected by CVE-2026-74381?


## How do I fix CVE-2026-74381?

Apply the vendor's patch.

## Is CVE-2026-74381 being exploited?

There is no known exploitation of CVE-2026-74381 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74381 and fix it if it is affected.

What it is: CVE-2026-74381 is an use after free 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-2026-74381 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-2026-74381/ (Markdown: https://insights.sbomify.com/CVE-2026-74381/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74381
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74381
- OSV: https://osv.dev/vulnerability/CVE-2026-74381

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74381/
Summaries are generated and may contain mistakes; the official description above is the record.