CVE-2024-42117

What it actually does

Functions searching for display configuration indices by plane or stream ID return -1 on failure, which is then used as an array index, enabling potential buffer overruns and invalid negative returns in AMD display code paths.

Why it matters to the business

Systems using affected Linux kernels with AMD graphics may experience display-related crashes or instability; low EPSS and absence from KEV indicate limited operational risk unless unpatched kernels remain in high-availability graphics workloads.

How an attack unfolds

An attacker with local access would need to force a display configuration lookup to fail for a given plane or stream ID, causing the -1 return value to propagate into array indexing; no named threat actors or ransomware campaigns are associated with this issue.

How to fix it

Update the Linux kernel to the fixed commit a9c047a5cf3135b8b66bd28fbe2c698b9cace0b3 or later stable release containing the ASSERT and positive return change.

How to confirm the fix worked

Confirm the running kernel contains commit a9c047a5cf3135b8b66bd28fbe2c698b9cace0b3; recompile with Coverity or equivalent static analysis to verify absence of the reported OVERRUN and NEGATIVE_RETURNS defects.

Typical attack path

1. Obtain local execution context on a vulnerable kernel
2. Trigger display plane or stream configuration lookup failure
3. Force use of invalid negative index in array access
4. Induce overrun or negative return behavior

How to detect it

Review kernel logs for ASSERT failures or display configuration errors around plane and stream ID lookups; no public exploitation artifacts are known given the low EPSS and lack of KEV listing.

What your security team should do

• Prioritize kernel updates for systems with AMD GPUs in production graphics workloads
• Monitor upstream stable kernel releases for backports
• Apply defense-in-depth by restricting unprivileged local access where feasible