# CVE-2026-53138: drm/amd/display: Bound VBIOS record-chain walk loops

> A malformed VBIOS image causes unbounded loops and out-of-bounds reads in the AMD display driver, leading to system hangs or crashes during probe.

- **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:** 25 Jun 2026
- **Updated:** 4 Jul 2026
- **Also known as:** AZL-90597, BELL-CVE-2026-53138, DEBIAN-CVE-2026-53138, GHSA-qc6f-vg59-3945, ROOT-OS-DEBIAN-11-CVE-2026-53138, ROOT-OS-DEBIAN-12-CVE-2026-53138, ROOT-OS-UBUNTU-2204-CVE-2026-53138, ROOT-OS-UBUNTU-2404-CVE-2026-53138, UBUNTU-CVE-2026-53138

## What is CVE-2026-53138?

CVE-2026-53138 is a high-severity denial of service vulnerability in Linux kernel, published on 25 Jun 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/amd/display: Bound VBIOS record-chain walk loops

[Why & How]
All record-chain walk loops in bios_parser.c and bios_parser2.c use
for(;;) and only terminate on a 0xFF record_type sentinel or zero
record_size. A malformed VBIOS image missing the terminator record
causes unbounded iteration at probe time, potentially hundreds of
thousands of iterations with record_size=1. In the final iterations
near the BIOS image boundary, struct casts beyond the 2-byte header
validated by GET_IMAGE can also read out of bounds.

Cap all 14 record-chain walk loops to BIOS_MAX_NUM_RECORD (256)
iterations. The atombios.h defines up to 22 distinct record types
and atomfirmware.h has 13. Assuming an average of less than 10
records per type (which is reasonable since most are connector-
based) 256 is a generous upper bound.

(cherry picked from commit 95700a3d660287ed657d6892f7be9ffc0e294a93)

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-53138?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-53138?

Apply the vendor's patch.

## Is CVE-2026-53138 being exploited?

There is no known exploitation of CVE-2026-53138 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-53138 and fix it if it is affected.

What it is: CVE-2026-53138 is a high-severity denial of service vulnerability in Linux kernel, published on 25 Jun 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-2026-53138 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2026-53138/ (Markdown: https://insights.sbomify.com/CVE-2026-53138/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53138
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53138
- OSV: https://osv.dev/vulnerability/CVE-2026-53138

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53138/
Summaries are generated and may contain mistakes; the official description above is the record.