CVE-2024-27418

What it actually does

The mctp_local_output function in the Linux kernel fails to consistently take ownership of the skb on error paths before routing occurs, resulting in skb leaks and potential memory corruption from unreleased socket buffers.

Why it matters to the business

Linux-based systems using MCTP networking may experience gradual memory exhaustion or instability, increasing operational risk for affected devices and requiring prioritized patching to avoid service degradation.

How an attack unfolds

An attacker triggers specific error conditions in mctp_local_output through crafted network input or state manipulation to cause skb leaks without triggering the route action, leading to resource exhaustion.

How to fix it

Update the Linux kernel to the fixed commit a3c8fa54e904b0ddb52a08cc2d8ac239054f61fd in the stable repository; apply the patch or upgrade to a distribution kernel containing this change.

How to confirm the fix worked

Verify the running kernel includes commit a3c8fa54e904b0ddb52a08cc2d8ac239054f61fd via git log or version strings; test mctp_local_output error paths to confirm skb is always freed.

Typical attack path

1. Identify systems running vulnerable Linux kernel versions with MCTP enabled
2. Send specially crafted packets or manipulate network states to invoke mctp_local_output error paths
3. Repeat to accumulate leaked skbs and exhaust kernel memory
4. Cause system instability or denial of service

How to detect it

Inspect kernel memory statistics and logs for unusual skb or MCTP allocation patterns; review network traffic and error paths around mctp_local_output for signs of repeated failures without cleanup.

What your security team should do

• Apply the kernel fix immediately due to memory corruption impact
• Monitor for MCTP-related memory usage anomalies
• Review and restrict MCTP usage where not required
• Test patched kernels in staging environments before production deployment