# CVE-2025-40232: rv: Fully convert enabled_monitors to use list_head as iterator

> A type casting error in the Linux kernel's rv subsystem causes a system crash, leading to denial of service for local attackers.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 4 Dec 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2025-40232, GHSA-rxcq-c8g5-8g6j, UBUNTU-CVE-2025-40232, USN-7920-1, USN-7920-2

## What is CVE-2025-40232?

CVE-2025-40232 is a vulnerability in Linux, published on 4 Dec 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:

rv: Fully convert enabled_monitors to use list_head as iterator

The callbacks in enabled_monitors_seq_ops are inconsistent. Some treat the
iterator as struct rv_monitor *, while others treat the iterator as struct
list_head *.

This causes a wrong type cast and crashes the system as reported by Nathan.

Convert everything to use struct list_head * as iterator. This also makes
enabled_monitors consistent with available_monitors.

## Which versions are affected by CVE-2025-40232?


## How do I fix CVE-2025-40232?

Apply the vendor's patch.

## Is CVE-2025-40232 being exploited?

There is no known exploitation of CVE-2025-40232 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-40232 and fix it if it is affected.

What it is: CVE-2025-40232 is a vulnerability in Linux, published on 4 Dec 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-2025-40232 in the wild and no public exploit code.

Affected product: Linux. 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-2025-40232/ (Markdown: https://insights.sbomify.com/CVE-2025-40232/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-40232
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-40232
- OSV: https://osv.dev/vulnerability/CVE-2025-40232

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-40232/
Summaries are generated and may contain mistakes; the official description above is the record.