CVE-2023-52483 mctp: perform route lookups under a RCU read-side lock
A race condition in Linux kernel MCTP route lookups allows use-after-free, potentially enabling local privilege escalation or code execution.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-52483?
CVE-2023-52483 is a high-severity use after free vulnerability in Linux kernel, published on 29 Feb 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
mctp: perform route lookups under a RCU read-side lock
Our current route lookups (mctp_route_lookup and mctp_route_lookup_null) traverse the net's route list without the RCU read lock held. This means the route lookup is subject to preemption, resulting in an potential grace period expiry, and so an eventual kfree() while we still have the route pointer.
Add the proper read-side critical section locks around the route lookups, preventing premption and a possible parallel kfree.
The remaining net->mctp.routes accesses are already under a rcu_read_lock, or protected by the RTNL for updates.
Based on an analysis from Sili Luo <[email protected]>, where introducing a delay in the route lookup could cause a UAF on simultaneous sendmsg() and route deletion.
Weakness: CWE-416
Which versions are affected by CVE-2023-52483?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2023-52483?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2023-52483 being exploited?
There is no known exploitation of CVE-2023-52483 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2023-52483, DEBIAN-CVE-2023-52483, GHSA-p8h7-jc93-wgq3, UBUNTU-CVE-2023-52483.