CVE-2024-38635

What it actually does

Incorrect PDI offset calculation in the soundwire cadence driver causes out-of-bounds array access in the Linux kernel memory.

Why it matters to the business

Kernel memory corruption on Linux systems can lead to crashes, data loss, or local privilege escalation, impacting stability and security of servers, desktops, and embedded devices using affected kernels.

How an attack unfolds

A local attacker triggers the soundwire cadence code path that applies an erroneous offset when indexing the PDI array, resulting in out-of-bounds memory access that can be leveraged for corruption or further exploitation.

How to fix it

Upgrade the Linux kernel to version 5.4.278 or later, or apply commit 002364b2d594a9afc0385c09e00994c510b1d089 from the stable git repository.

How to confirm the fix worked

Confirm the running kernel version meets or exceeds 5.4.278; verify the presence of commit 002364b2d594a9afc0385c09e00994c510b1d089 in the kernel source tree.

Typical attack path

1. Obtain local user access on a vulnerable Linux system
2. Trigger audio or soundwire operations that invoke the PDI offset logic
3. Exploit the resulting out-of-bounds access to corrupt kernel memory or escalate privileges

How to detect it

Inspect kernel logs and oops reports for references to soundwire cadence PDI out-of-bounds conditions; no widespread exploitation artifacts are known.

What your security team should do

• Prioritize kernel upgrades across all affected Linux deployments
• Limit local user access on systems handling sensitive workloads until patched
• Monitor kernel logs for soundwire or cadence related faults during the update window