drm/vc4: Prevent shader BO mappings from becoming writable (CVE-2026-68445) | HOL Guard CVE

High · CVSS 7.8CVE-2026-68445

drm/vc4: Prevent shader BO mappings from becoming writable

Answer in brief

CVE-2026-68445 records a High severity (CVSS 7.8) vulnerability in drm/vc4: Prevent shader BO mappings from becoming writable. 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 Aug 12, 2026Updated Aug 17, 2026Source checked Sep 26, 2026First seen by HOL Aug 12, 2026Material review Aug 17, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.8
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 7.8. 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	>=463873d5701427f2964a0b4b72c45f1f14b6df87 <9f0ee411fc2d76333d6087c5862ffa907cf7a175 \|\| >=463873d5701427f2964a0b4b72c45f1f14b6df87 <019e6ad247f7fd038d2e009789f6d9bfcccb1ae7 \|\| >=463873d5701427f2964a0b4b72c45f1f14b6df87 <6deaa317201851c644c431b57682e54d06b35838 \|\| >=463873d5701427f2964a0b4b72c45f1f14b6df87 <fe168ef1d232d734d9998fd74822e2e20930dfff \|\| >=463873d5701427f2964a0b4b72c45f1f14b6df87 <0c9e6367639548307d3f578f6943ce72c9d39087	9f0ee411fc2d76333d6087c5862ffa907cf7a175, 019e6ad247f7fd038d2e009789f6d9bfcccb1ae7, 6deaa317201851c644c431b57682e54d06b35838, fe168ef1d232d734d9998fd74822e2e20930dfff, 0c9e6367639548307d3f578f6943ce72c9d39087
Linux/Linuxgeneric	4.5	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 9f0ee411fc2d76333d6087c5862ffa907cf7a175 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 12, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 12, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: drm/vc4: Prevent shader BO mappings from becoming writable vc4_gem_object_mmap() rejects a writable mapping of a validated shader BO, but leaves VM_MAYWRITE set. Userspace can map the BO read-only and then turn it writable with mprotect(). Validated shader BOs must stay read-only: the validator checks the instructions once and the GPU trusts them afterwards. A writable mapping lets userspace rewrite the code after validation, bypassing the validator. Clear VM_MAYWRITE on the read-only path so the mapping cannot be upgraded, as i915 already does for its read-only objects.

Quoted source text, attributed separately from HOL analysis.