CVE-2023-52512

What it actually does

An out-of-bounds write occurs in the pinctrl driver when an invalid GPIO index is processed before validation, allowing memory corruption in the kernel.

Why it matters to the business

Systems running affected Linux kernels may experience instability, crashes, or potential unauthorized code execution, leading to downtime or security breaches. With nearly three years since disclosure and low exploitation probability, immediate widespread impact is unlikely but patching remains essential for compliance.

How an attack unfolds

An attacker with local access crafts input to the pinctrl nuvoton wpcm450 driver using an out-of-range GPIO index, causing the write to gpio_bank to occur before the bounds check, resulting in memory corruption that could be leveraged for privilege escalation.

How to fix it

Update the Linux kernel to a version containing commit 6c18c386fd13dbb3ff31a1086dabb526780d9bda or later.

How to confirm the fix worked

Verify the kernel source includes the fix commit or check for the presence of the bounds check before the write operation.

Typical attack path

1. Obtain local access to the system
2. Trigger the vulnerable pinctrl code path with invalid GPIO index
3. Exploit resulting memory corruption for further access

How to detect it

Examine system logs for kernel oops or panics related to pinctrl, and audit access logs for unusual GPIO operations.

What your security team should do

• Apply the kernel patch immediately if using affected versions
• Monitor for any new exploit developments despite low EPSS
• Test in staging environments before production rollout