# CVE-2022-2652: Use of Externally-Controlled Format String in umlaeute/v4l2loopback

> Crafted format strings in v4l2loopback card labels allow attackers to leak kernel stack memory and cause denial of service via module crashes.

- **Severity:** High 7.3 (`CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 4 Aug 2022
- **Updated:** 3 Aug 2024
- **Also known as:** DEBIAN-CVE-2022-2652, GHSA-grx9-955g-vjfg, UBUNTU-CVE-2022-2652, openSUSE-SU-2022:10159-1, openSUSE-SU-2022:10160-1, openSUSE-SU-2024:12372-1

## What is CVE-2022-2652?

CVE-2022-2652 is a high-severity vulnerability in umlaeute/v4l2loopback, published on 4 Aug 2022. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Depending on the way the format strings in the card label are crafted it's possible to leak kernel stack memory. There is also the possibility for DoS due to the v4l2loopback kernel module crashing when providing the card label on request (reproduce e.g. with many %s modifiers in a row).

Weakness: CWE-134 (Use of Externally-Controlled Format String)

## Which versions are affected by CVE-2022-2652?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `v4l2loopback` | openSUSE:Leap 15.3 | All versions | 0.12.5-lp153.2.5.1 |
| `v4l2loopback` | openSUSE:Leap 15.4 | All versions | 0.12.5-lp154.3.3.1 |

Products: V4l2loopback Project V4l2loopback.

## How do I fix CVE-2022-2652?

Apply the vendor's patch.

## Is CVE-2022-2652 being exploited?

There is no known exploitation of CVE-2022-2652 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-2652 and fix it if it is affected.

What it is: CVE-2022-2652 is a high-severity vulnerability in umlaeute/v4l2loopback, published on 4 Aug 2022. 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-2022-2652 in the wild and no public exploit code.

Affected product: umlaeute/v4l2loopback. 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-2022-2652/ (Markdown: https://insights.sbomify.com/CVE-2022-2652/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-2652
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-2652
- OSV: https://osv.dev/vulnerability/CVE-2022-2652

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-2652/
Summaries are generated and may contain mistakes; the official description above is the record.