# CVE-2026-55251: Code injection in devicetype-library

> Attackers can execute arbitrary code on CI runners by submitting malicious configuration files in pull requests to the NetBox Device Type Library.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 Oct 2026
- **Updated:** 5 Oct 2026
- **Also known as:** GHSA-5x2m-x42f-g4cm

## What is CVE-2026-55251?

CVE-2026-55251 is a medium-severity code injection vulnerability in netbox-community devicetype-library, published on 1 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

NetBox Device Type Library is a collection of community-sourced device type definitions for import into NetBox. Prior to commit f41fc1e, the CI workflow .github/workflows/validation.yml runs on pull_request and executes code supplied by the pull request before any maintainer review. Three PR-editable files drive this: "requirements.txt", ".pre-commit-hooks-config.yaml" / ".pre-commit-yamlfmt-config.yaml", and ".gitmodules". A contributor with no special repository access could open a pull request that modifies these files and have their code run on the CI runner. This issue has been patched via commit f41fc1e.

Weakness: CWE-94 (Improper Control of Generation of Code), CWE-829 (Inclusion of Functionality from Untrusted Control Sphere), CWE-494 (Download of Code Without Integrity Check)

## Which versions are affected by CVE-2026-55251?


## How do I fix CVE-2026-55251?

No fix has been published for CVE-2026-55251 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-55251 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55251 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-55251 and fix it if it is affected.

What it is: CVE-2026-55251 is a medium-severity code injection vulnerability in netbox-community devicetype-library, published on 1 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55251 exists.

Affected product: netbox-community devicetype-library. 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-2026-55251/ (Markdown: https://insights.sbomify.com/CVE-2026-55251/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-55251
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-55251
- OSV: https://osv.dev/vulnerability/CVE-2026-55251

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-55251/
Summaries are generated and may contain mistakes; the official description above is the record.