# CVE-2025-38567: nfsd: avoid ref leak in nfsd_open_local_fh()

> A race condition in the Linux kernel NFS server causes a reference leak, leading to a hang during shutdown and denial of service.

- **Severity:** Medium 4.7 (`CVSS:3.1/AV:L/AC:H/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:** 19 Aug 2025
- **Updated:** 23 May 2026
- **Also known as:** BELL-CVE-2025-38567, GHSA-36x9-553r-v339, UBUNTU-CVE-2025-38567

## What is CVE-2025-38567?

CVE-2025-38567 is a medium-severity vulnerability in Linux kernel, published on 19 Aug 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:

nfsd: avoid ref leak in nfsd_open_local_fh()

If two calls to nfsd_open_local_fh() race and both successfully call
nfsd_file_acquire_local(), they will both get an extra reference to the
net to accompany the file reference stored in *pnf.

One of them will fail to store (using xchg()) the file reference in
*pnf and will drop that reference but WON'T drop the accompanying
reference to the net.  This leak means that when the nfs server is shut
down it will hang in nfsd_shutdown_net() waiting for
&nn->nfsd_net_free_done.

This patch adds the missing nfsd_net_put().

Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2025-38567?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-38567?

Apply the vendor's patch.

## Is CVE-2025-38567 being exploited?

There is no known exploitation of CVE-2025-38567 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-2025-38567 and fix it if it is affected.

What it is: CVE-2025-38567 is a medium-severity vulnerability in Linux kernel, published on 19 Aug 2025. 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-2025-38567 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-2025-38567/ (Markdown: https://insights.sbomify.com/CVE-2025-38567/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38567
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38567
- OSV: https://osv.dev/vulnerability/CVE-2025-38567

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38567/
Summaries are generated and may contain mistakes; the official description above is the record.