# 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.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **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:** Yes
- **Published:** 25 Mar 2026
- **Updated:** 23 May 2026
- **Also known as:** BELL-CVE-2026-23376, DEBIAN-CVE-2026-23376, GHSA-36q5-3685-99hr, UBUNTU-CVE-2026-23376

## 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: 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

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-23376 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2026-23376 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-23376/ (Markdown: https://insights.sbomify.com/CVE-2026-23376/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-23376
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-23376
- OSV: https://osv.dev/vulnerability/CVE-2026-23376

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-23376/
Summaries are generated and may contain mistakes; the official description above is the record.