CVE-2023-53987 ping: Fix potentail NULL deref for /proc/net/icmp.
A local attacker can trigger a NULL pointer dereference in the Linux kernel's ping socket handling, causing a system crash.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-53987?
CVE-2023-53987 is a 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:
ping: Fix potentail NULL deref for /proc/net/icmp.
After commit dbca1596bbb0 ("ping: convert to RCU lookups, get rid of rwlock"), we use RCU for ping sockets, but we should use spinlock for /proc/net/icmp to avoid a potential NULL deref mentioned in the previous patch.
Let's go back to using spinlock there.
Note we can convert ping sockets to use hlist instead of hlist_nulls because we do not use SLAB_TYPESAFE_BY_RCU for ping sockets.
Which versions are affected by CVE-2023-53987?
How do I fix CVE-2023-53987?
Apply the vendor's patch.
Is CVE-2023-53987 being exploited?
There is no known exploitation of CVE-2023-53987 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-53987, DEBIAN-CVE-2023-53987, GHSA-m6qc-r2rx-cm2q, UBUNTU-CVE-2023-53987.