# CVE-2026-74447: drm/amdkfd: fix uint32_t overflow in EOP ring buffer size alignment

> A local attacker can trigger an integer overflow in the AMD KFD driver, causing GPU faults and denial of service.

- **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:** BELL-CVE-2026-74447, DEBIAN-CVE-2026-74447, GHSA-hxwh-98gw-89f6, UBUNTU-CVE-2026-74447

## What is CVE-2026-74447?

CVE-2026-74447 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: fix uint32_t overflow in EOP ring buffer size alignment

eop_ring_buffer_size in struct queue_properties is a u32. In
kfd_queue_acquire_buffers() the expected EOP buffer size is computed as
ALIGN(eop_ring_buffer_size, PAGE_SIZE); ALIGN uses typeof(x), so the
addition is done in 32-bit. A user-supplied size of 0xFFFFF001 wraps to
0, causing kfd_queue_buffer_get() to skip its exact-size check (gated on
size != 0) and accept any BO mapped at the address. On GFX8/GFX9 the MQD
cp_hqd_eop_control is then programmed for an 8KB EOP ring backed by a 4KB
BO, so CP EOP writes can land past the buffer and fault the GPU.

Cast the operand to u64 so the alignment is computed in 64-bit; the size
check in kfd_queue_buffer_get() then rejects the oversized request.

(cherry picked from commit ae443117b742c357bfef3a7bddabf76fcf86e9ef)

## Which versions are affected by CVE-2026-74447?


## How do I fix CVE-2026-74447?

Apply the vendor's patch.

## Is CVE-2026-74447 being exploited?

There is no known exploitation of CVE-2026-74447 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74447 and fix it if it is affected.

What it is: CVE-2026-74447 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-2026-74447 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-2026-74447/ (Markdown: https://insights.sbomify.com/CVE-2026-74447/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74447
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74447
- OSV: https://osv.dev/vulnerability/CVE-2026-74447

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74447/
Summaries are generated and may contain mistakes; the official description above is the record.