CVE-2023-54033 bpf: fix a memory leak in the LRU and LRU_PERCPU hash maps
A memory leak in Linux kernel BPF LRU maps allows local attackers to exhaust memory, causing denial of service.
- 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-2023-54033?
CVE-2023-54033 is a memory corruption vulnerability in Linux, published on 24 Dec 2025. 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:
bpf: fix a memory leak in the LRU and LRU_PERCPU hash maps
The LRU and LRU_PERCPU maps allocate a new element on update before locking the target hash table bucket. Right after that the maps try to lock the bucket. If this fails, then maps return -EBUSY to the caller without releasing the allocated element. This makes the element untracked: it doesn't belong to either of free lists, and it doesn't belong to the hash table, so can't be re-used; this eventually leads to the permanent -ENOMEM on LRU map updates, which is unexpected. Fix this by returning the element to the local free list if bucket locking fails.
Which versions are affected by CVE-2023-54033?
How do I fix CVE-2023-54033?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2023-54033 being exploited?
There is no known exploitation of CVE-2023-54033 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-54033, DEBIAN-CVE-2023-54033, GHSA-hcpj-xwwg-jgh9, UBUNTU-CVE-2023-54033.