# CVE-2026-89826: drm/panthor: harden firmware build-info bounds checks

> Integer overflow in Panthor GPU driver allows bypassing bounds checks, potentially leading to out-of-bounds reads and code execution.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/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:** 16 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-89826, DEBIAN-CVE-2026-89826, GHSA-vfmm-vgxh-2c77, UBUNTU-CVE-2026-89826

## What is CVE-2026-89826?

CVE-2026-89826 is a high-severity vulnerability in Linux, published on 16 Sep 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/panthor: harden firmware build-info bounds checks

panthor_fw_read_build_info() checks whether the metadata range fits in the
firmware image with hdr.meta_start + hdr.meta_size. Both fields are u32, so
the addition can wrap and let an out-of-bounds range pass validation.

The function also reads the "git_sha: " prefix without first checking that
the metadata is long enough, and meta_size == 0 can underflow the NULL
terminator index.

Use subtraction-based bounds checking and reject metadata that is too short
to contain the expected prefix and trailing NULL byte.

## Which versions are affected by CVE-2026-89826?


## How do I fix CVE-2026-89826?

Apply the vendor's patch.

## Is CVE-2026-89826 being exploited?

There is no known exploitation of CVE-2026-89826 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-89826 and fix it if it is affected.

What it is: CVE-2026-89826 is a high-severity vulnerability in Linux, published on 16 Sep 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-2026-89826 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-2026-89826/ (Markdown: https://insights.sbomify.com/CVE-2026-89826/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-89826
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-89826
- OSV: https://osv.dev/vulnerability/CVE-2026-89826

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-89826/
Summaries are generated and may contain mistakes; the official description above is the record.