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.
- 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
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
Which versions are affected by CVE-2026-53138?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-53138?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
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
Sources
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 and 3 more.