CVE-2024-46818

What it actually does

The drm/amd/display code in the Linux kernel uses GPIO_ID_UNKNOWN (-1) as an array index without validation, enabling out-of-bounds memory access and five reported buffer overrun conditions.

Why it matters to the business

Systems running affected Linux kernels with AMD display hardware face elevated risk of crashes, instability, or local privilege escalation; high downstream prevalence of the kernel magnifies operational exposure for servers, workstations, and embedded devices.

How an attack unfolds

An attacker with local access supplies an invalid GPIO identifier that reaches the unchecked array indexing path in the AMD display driver, triggering memory corruption that can be chained for privilege escalation; listed threat actors in 2024-2025 Linux kernel campaigns illustrate ongoing interest in similar kernel flaws.

How to fix it

Update the Linux kernel to commit 8520fdc8ecc38f240a8e9e7af89cca6739c3e790 or later; rebuild and deploy the fixed kernel across all affected distributions and embedded images.

How to confirm the fix worked

Confirm the running kernel contains commit 8520fdc8ecc38f240a8e9e7af89cca6739c3e790; re-run static analysis tools such as Coverity on the display driver to verify absence of the five OVERRUN reports.

Typical attack path

1. Obtain local code execution on a target Linux system
2. Trigger AMD display GPIO handling code with GPIO_ID_UNKNOWN
3. Cause out-of-bounds array access leading to memory corruption
4. Leverage corruption for privilege escalation or denial of service

How to detect it

Review kernel logs for AMD display driver crashes or oops involving gpio handling; correlate with process execution of untrusted local binaries immediately preceding the event.

What your security team should do

• Prioritize kernel upgrades on all AMD GPU systems within the CISA-style remediation window
• Monitor for new stable releases containing the referenced commit
• Apply defense-in-depth by restricting untrusted local code execution