CVE-2025-40342 nvme-fc: use lock accessing port_state and rport state
A race condition in the Linux kernel NVMe FC driver allows attackers to cause a denial of service by triggering concurrent unregister and reconnect operations.
- 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-2025-40342?
CVE-2025-40342 is a high-severity vulnerability in Linux, published on 9 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:
nvme-fc: use lock accessing port_state and rport state
nvme_fc_unregister_remote removes the remote port on a lport object at any point in time when there is no active association. This races with with the reconnect logic, because nvme_fc_create_association is not taking a lock to check the port_state and atomically increase the active count on the rport.
Which versions are affected by CVE-2025-40342?
How do I fix CVE-2025-40342?
Apply the vendor's patch.
Is CVE-2025-40342 being exploited?
There is no known exploitation of CVE-2025-40342 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2025-40342, DEBIAN-CVE-2025-40342, GHSA-gvgm-wg7j-vj8f, ROOT-OS-DEBIAN-12-CVE-2025-40342, ROOT-OS-DEBIAN-13-CVE-2025-40342, ROOT-OS-UBUNTU-2204-CVE-2025-40342 and 2 more.