CVE-2026-23376 nvmet-fcloop: Check remoteport port_state before calling done callback
A missing state check in the Linux kernel NVMe FC loop driver can lead to a null pointer dereference and system crash.
- 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-2026-23376?
CVE-2026-23376 is a medium-severity vulnerability in Linux kernel, published on 25 Mar 2026. 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:
nvmet-fcloop: Check remoteport port_state before calling done callback
In nvme_fc_handle_ls_rqst_work, the lsrsp->done callback is only set when remoteport->port_state is FC_OBJSTATE_ONLINE. Otherwise, the nvme_fc_xmt_ls_rsp's LLDD call to lport->ops->xmt_ls_rsp is expected to fail and the nvme-fc transport layer itself will directly call nvme_fc_xmt_ls_rsp_free instead of relying on LLDD's done callback to free the lsrsp resources.
Update the fcloop_t2h_xmt_ls_rsp routine to check remoteport->port_state. If online, then lsrsp->done callback will free the lsrsp. Else, return -ENODEV to signal the nvme-fc transport to handle freeing lsrsp.
Which versions are affected by CVE-2026-23376?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-23376?
Apply the vendor's patch.
Is CVE-2026-23376 being exploited?
There is no known exploitation of CVE-2026-23376 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-23376, DEBIAN-CVE-2026-23376, GHSA-36q5-3685-99hr, UBUNTU-CVE-2026-23376.