# CVE-2026-68276: drm/amdgpu/gfx: fix cleaner shader IB buffer overflow

> A buffer overflow in the amdgpu cleaner shader allows local attackers to cause kernel crashes or potentially escalate privileges.

- **Severity:** Not scored
- **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:** 10 Aug 2026
- **Updated:** 17 Aug 2026
- **Also known as:** BELL-CVE-2026-68276, DEBIAN-CVE-2026-68276, GHSA-2f7w-jqwh-gfwp, UBUNTU-CVE-2026-68276

## What is CVE-2026-68276?

CVE-2026-68276 is a memory corruption vulnerability in Linux, published on 10 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/amdgpu/gfx: fix cleaner shader IB buffer overflow

The cleaner shader sysfs path allocates a 16-dword (64 byte) IB but
incorrectly fills (align_mask + 1) dwords. On GFX rings align_mask is
0xff, so the loop wrote 256 dwords into a 64-byte buffer, causing a
kernel page fault.

The IB only needs to be a minimal NOP shell to schedule the job; the
cleaner shader itself is emitted on the ring via emit_cleaner_shader().
Fill 16 dwords to match the allocation.

v2: Use ib_size_dw variable (Lijo)

(cherry picked from commit bf21af331ebf72d0935fd70c73192414a422c03a)

## Which versions are affected by CVE-2026-68276?


## How do I fix CVE-2026-68276?

Apply the vendor's patch.

## Is CVE-2026-68276 being exploited?

There is no known exploitation of CVE-2026-68276 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68276 and fix it if it is affected.

What it is: CVE-2026-68276 is a memory corruption vulnerability in Linux, published on 10 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-2026-68276 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-2026-68276/ (Markdown: https://insights.sbomify.com/CVE-2026-68276/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68276
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68276
- OSV: https://osv.dev/vulnerability/CVE-2026-68276

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68276/
Summaries are generated and may contain mistakes; the official description above is the record.