# CVE-2023-49291: Improper Sanitization of Branch Name Leads to Arbitrary Code Injection

> Attackers can execute arbitrary code and steal secrets by crafting malicious branch names in GitHub Actions workflows using the tj-actions/branch-names action.

- **Severity:** Critical 9.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 4 Dec 2023
- **Updated:** 2 Aug 2024
- **Also known as:** GHSA-8v8w-v8xg-79rf

## What is CVE-2023-49291?

CVE-2023-49291 is a critical code injection vulnerability in tj-actions branch-names, published on 4 Dec 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

tj-actions/branch-names is a Github action to retrieve branch or tag names with support for all events. The `tj-actions/branch-names` GitHub Actions improperly references the `github.event.pull_request.head.ref` and `github.head_ref` context variables within a GitHub Actions `run` step. The head ref variable is the branch name and can be used to execute arbitrary code using a specially crafted branch name. As a result an attacker can use this vulnerability to steal secrets from or abuse `GITHUB_TOKEN` permissions. This vulnerability has been addressed in version 7.0.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2023-49291?

1 open source package ship an affected version, including tj-actions/branch-names. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `tj-actions/branch-names` | GitHub Actions | All versions | 7.0.7 |

Products: Tj-Actions Branch-Names.

## How do I fix CVE-2023-49291?

Upgrade tj-actions/branch-names to 7.0.7 or later.

## Is CVE-2023-49291 being exploited?

There is no known exploitation of CVE-2023-49291 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-49291 and fix it if it is affected.

What it is: CVE-2023-49291 is a critical code injection vulnerability in tj-actions branch-names, published on 4 Dec 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-49291 in the wild and no public exploit code.

Affected packages and fixed versions:
- tj-actions/branch-names (GitHub Actions): affected all versions; fixed in 7.0.7

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-2023-49291/ (Markdown: https://insights.sbomify.com/CVE-2023-49291/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-49291
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-49291
- OSV: https://osv.dev/vulnerability/CVE-2023-49291

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-49291/
Summaries are generated and may contain mistakes; the official description above is the record.