# CVE-2026-74446: drm/amdkfd: hold event_mutex while checkpointing CRIU events

> A race condition in the Linux kernel's AMD KFD driver allows out-of-bounds writes or use-after-free during CRIU checkpointing, potentially leading to privilege escalation.

- **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:** 16 Oct 2026
- **Also known as:** AZL-96108, BELL-CVE-2026-74446, DEBIAN-CVE-2026-74446, GHSA-3f2f-q78g-jqw3, UBUNTU-CVE-2026-74446

## What is CVE-2026-74446?

CVE-2026-74446 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:

drm/amdkfd: hold event_mutex while checkpointing CRIU events

kfd_criu_checkpoint_events() counts the entries in p->event_idr via
kfd_get_num_events(), allocates an array sized to that count, and then
walks the same IDR to fill it. Neither the count nor the walk holds
p->event_mutex.

The CRIU checkpoint caller holds only p->mutex. Event create and destroy
(kfd_event_create()/kfd_event_destroy()) take p->event_mutex and do not
take p->mutex, so a second thread in the same process can insert or remove
events between the count and the walk. If an event is inserted, the walk
iterates more entries than were counted and writes past the end of the
ev_privs allocation; if an event is removed, the walk dereferences an
entry that is being freed.

Hold p->event_mutex across the count and the walk so both observe a
consistent view of p->event_idr. The lock is released before
copy_to_user(), which only touches the local buffer. The caller already
holds p->mutex and the create/destroy paths never take p->mutex, so the
p->mutex -> p->event_mutex order is not inverted and no deadlock is
introduced.

(cherry picked from commit ff57e223ab105795b05d3ef3f3c35a5a441bcbaa)

## Which versions are affected by CVE-2026-74446?


## How do I fix CVE-2026-74446?

Apply the vendor's patch.

## Is CVE-2026-74446 being exploited?

There is no known exploitation of CVE-2026-74446 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74446 and fix it if it is affected.

What it is: CVE-2026-74446 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-2026-74446 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-2026-74446/ (Markdown: https://insights.sbomify.com/CVE-2026-74446/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74446
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74446
- OSV: https://osv.dev/vulnerability/CVE-2026-74446

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74446/
Summaries are generated and may contain mistakes; the official description above is the record.