CVE-2026-53138: In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Bound VBIOS record-chain walk loops [Why & How] All record-chai...

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)

Metrics

EPSS Probability

0.17%

6.4th percentile

Probability of exploitation in the next 30 days. Learn more

References

Timeline

Published: Jun 25, 2026
Last Modified: Jun 25, 2026
Status: Received

Frequently Asked Questions

What is CVE-2026-53138?

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)

How severe is CVE-2026-53138?

Severity scoring for CVE-2026-53138 is pending analysis. The EPSS model estimates a 0.17% probability of exploitation in the next 30 days.

How do I fix CVE-2026-53138?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.