drm/amd/display: Fix out-of-bound accesses

Answer in brief

CVE-2025-21985 records a Unknown severity vulnerability in drm/amd/display: Fix out-of-bound accesses. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Apr 1, 2025Updated Aug 5, 2026Source checked Sep 19, 2026First seen by HOL Aug 5, 2026Material review Aug 5, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=4562236b3bc0a28aeb6ee93b2d8a849a4c4e1c7c <36793d90d76f667d26c6dd025571481ee0c96abc \|\| >=4562236b3bc0a28aeb6ee93b2d8a849a4c4e1c7c <9aedc776b11038f04f4641241bb7e877781e4aa4 \|\| >=4562236b3bc0a28aeb6ee93b2d8a849a4c4e1c7c <8adbb2a98b00926315fd513b5fe2596b5716b82d	36793d90d76f667d26c6dd025571481ee0c96abc, 9aedc776b11038f04f4641241bb7e877781e4aa4, 8adbb2a98b00926315fd513b5fe2596b5716b82d
Linux/Linuxgeneric	4.15	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 36793d90d76f667d26c6dd025571481ee0c96abc if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Apr 1, 2025
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 5, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix out-of-bound accesses [WHAT & HOW] hpo_stream_to_link_encoder_mapping has size MAX_HPO_DP2_ENCODERS(=4), but location can have size up to 6. As a result, it is necessary to check location against MAX_HPO_DP2_ENCODERS. Similiarly, disp_cfg_stream_location can be used as an array index which should be 0..5, so the ASSERT's conditions should be less without equal.

Quoted source text, attributed separately from HOL analysis.