CVE-2023-52483

What it actually does

Race condition in MCTP route lookups allows use-after-free when a route is deleted during lookup, due to missing RCU read-side lock, potentially leading to kernel memory corruption or crash.

Why it matters to the business

Systems running affected Linux kernels may experience crashes or, in rare cases, allow local attackers to escalate privileges, impacting system stability and security in environments using MCTP networking.

How an attack unfolds

An attacker with local access performs concurrent operations: one thread sends a message triggering route lookup while another deletes the route, exploiting the window without RCU protection to cause UAF.

How to fix it

Update the Linux kernel to a version containing commit 6c52b12159049046483fdb0c411a0a1869c41a67 or later.

How to confirm the fix worked

Verify the kernel source includes the RCU read lock around mctp_route_lookup calls; check for the commit in the git history.

Typical attack path

1. Gain local access to the system
2. Identify MCTP route usage
3. Trigger concurrent sendmsg and route deletion operations
4. Exploit resulting UAF for memory corruption or code execution

How to detect it

Look for kernel logs indicating use-after-free in mctp_route_lookup or related functions; monitor for unexpected crashes during network operations involving MCTP.

What your security team should do

• Prioritize kernel updates on systems using MCTP
• Monitor for kernel oops related to MCTP
• Restrict local access where possible until patched