# CVE-2022-50241: NFSD: fix use-after-free on source server when doing inter-server copy

> A use-after-free vulnerability in the Linux kernel's NFSD allows attackers to cause denial of service or potentially execute code via inter-server copy operations.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 15 Sep 2025
- **Updated:** 15 Oct 2026
- **Also known as:** DEBIAN-CVE-2022-50241, GHSA-wc22-wv2f-7f64, UBUNTU-CVE-2022-50241

## What is CVE-2022-50241?

CVE-2022-50241 is a high-severity use after free vulnerability in Linux kernel, published on 15 Sep 2025. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

NFSD: fix use-after-free on source server when doing inter-server copy

Use-after-free occurred when the laundromat tried to free expired
cpntf_state entry on the s2s_cp_stateids list after inter-server
copy completed. The sc_cp_list that the expired copy state was
inserted on was already freed.

When COPY completes, the Linux client normally sends LOCKU(lock_state x),
FREE_STATEID(lock_state x) and CLOSE(open_state y) to the source server.
The nfs4_put_stid call from nfsd4_free_stateid cleans up the copy state
from the s2s_cp_stateids list before freeing the lock state's stid.

However, sometimes the CLOSE was sent before the FREE_STATEID request.
When this happens, the nfsd4_close_open_stateid call from nfsd4_close
frees all lock states on its st_locks list without cleaning up the copy
state on the sc_cp_list list. When the time the FREE_STATEID arrives the
server returns BAD_STATEID since the lock state was freed. This causes
the use-after-free error to occur when the laundromat tries to free
the expired cpntf_state.

This patch adds a call to nfs4_free_cpntf_statelist in
nfsd4_close_open_stateid to clean up the copy state before calling
free_ol_stateid_reaplist to free the lock state's stid on the reaplist.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2022-50241?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-50241?

Apply the vendor's patch.

## Is CVE-2022-50241 being exploited?

There is no known exploitation of CVE-2022-50241 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-2022-50241 and fix it if it is affected.

What it is: CVE-2022-50241 is a high-severity use after free vulnerability in Linux kernel, published on 15 Sep 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-50241 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-2022-50241/ (Markdown: https://insights.sbomify.com/CVE-2022-50241/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-50241
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-50241
- OSV: https://osv.dev/vulnerability/CVE-2022-50241

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-50241/
Summaries are generated and may contain mistakes; the official description above is the record.