# CVE-2025-22026: nfsd: don't ignore the return code of svc_proc_register()

> An attacker can cause a kernel warning and potential instability by triggering a failure in NFS proc file registration, requiring a kernel patch.

- **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:** 16 Apr 2025
- **Updated:** 19 Jun 2026
- **Also known as:** AZL-62735, AZL-68985, BELL-CVE-2025-22026, DEBIAN-CVE-2025-22026, GHSA-xrr8-p4pf-hfwr, ROOT-OS-DEBIAN-11-CVE-2025-22026, ROOT-OS-DEBIAN-12-CVE-2025-22026, ROOT-OS-UBUNTU-2204-CVE-2025-22026, ROOT-OS-UBUNTU-2404-CVE-2025-22026, UBUNTU-CVE-2025-22026

## What is CVE-2025-22026?

CVE-2025-22026 is a medium-severity denial of service vulnerability in Linux kernel, published on 16 Apr 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: don't ignore the return code of svc_proc_register()

Currently, nfsd_proc_stat_init() ignores the return value of
svc_proc_register(). If the procfile creation fails, then the kernel
will WARN when it tries to remove the entry later.

Fix nfsd_proc_stat_init() to return the same type of pointer as
svc_proc_register(), and fix up nfsd_net_init() to check that and fail
the nfsd_net construction if it occurs.

svc_proc_register() can fail if the dentry can't be allocated, or if an
identical dentry already exists. The second case is pretty unlikely in
the nfsd_net construction codepath, so if this happens, return -ENOMEM.

Weakness: CWE-252 (Unchecked Return Value)

## Which versions are affected by CVE-2025-22026?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-22026?

Apply the vendor's patch.

## Is CVE-2025-22026 being exploited?

There is no known exploitation of CVE-2025-22026 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-2025-22026 and fix it if it is affected.

What it is: CVE-2025-22026 is a medium-severity denial of service vulnerability in Linux kernel, published on 16 Apr 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-2025-22026 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-2025-22026/ (Markdown: https://insights.sbomify.com/CVE-2025-22026/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-22026
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-22026
- OSV: https://osv.dev/vulnerability/CVE-2025-22026

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-22026/
Summaries are generated and may contain mistakes; the official description above is the record.