CVE-2026-53138
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)
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ if you've already worked around this in production โ publish your fix to the community-verified tier.
โ Propose a mitigation on Community โ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
Debian Mixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 6.12.94-1 |
| sid | Fixed | 7.0.13-1 |
| forky | Affected | โ |
| bullseye | Affected | โ |
| bookworm | Affected | โ |
References
- https://git.kernel.org/stable/c/6173cfea2f916e01c4f98e29cd654384a05e32a3
- https://git.kernel.org/stable/c/0e56f460bddb397fa9a8e6faf7ae7eaa86953eb1
- https://git.kernel.org/stable/c/2645e3caf7e013189da9c6ff621d006cca5a538b
- https://git.kernel.org/stable/c/ff287df16a1a58aca78b08d1f3ee09fc44da0351
- https://security-tracker.debian.org/tracker/CVE-2026-53138
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.