# GHSA-mj96-mh85-r574: buildalon/setup-steamcmd leaked authentication token in job output logs

> The setup-steamcmd action leaks Steam authentication tokens in public logs, allowing attackers to hijack accounts and access sensitive data.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 21 Jul 2025

## What is GHSA-mj96-mh85-r574?

GHSA-mj96-mh85-r574 is a vulnerability in buildalon/setup-steamcmd, published on 21 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

### Summary
Log output includes authentication token that provides full account access

### Details
The post job action prints the contents of `config/config.vdf` which holds the saved authentication token and can be used to sign in on another machine. This means any public use of this action leaves authentication tokes for the associated steam accounts publicly available. Additionally, `userdata/$user_id$/config/localconfig.vdf` contains potentially sensitive information which should not be included in public logs.

### PoC
Use the following workflow step
```
steps:
      - name: Setup SteamCMD
        uses: buildalon/setup-steamcmd@v1.0.4

      - name: Sign into steam
        shell: bash
        run: |
          steamcmd +login ${{ secrets.WORKSHOP_USERNAME }} ${{ secrets.WORKSHOP_PASSWORD }} +quit
```

### Impact
Anyone who has used this workflow action with a steam account is affected and has had valid authentication tokens leaked in the job logs. This is particularly bad for public repositories, as anyone with a GitHub account can access the logs and view the token.

## Which versions are affected by GHSA-mj96-mh85-r574?

1 open source package ship an affected version, including buildalon/setup-steamcmd.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `buildalon/setup-steamcmd` | GitHub Actions | All versions | 1.1.0 |

## How do I fix GHSA-mj96-mh85-r574?

Upgrade buildalon/setup-steamcmd to 1.1.0 or later.

## Is GHSA-mj96-mh85-r574 being exploited?

There is no known exploitation of GHSA-mj96-mh85-r574 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-mj96-mh85-r574 and fix it if it is affected.

What it is: GHSA-mj96-mh85-r574 is a vulnerability in buildalon/setup-steamcmd, published on 21 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of GHSA-mj96-mh85-r574 in the wild and no public exploit code.

Affected packages and fixed versions:
- buildalon/setup-steamcmd (GitHub Actions): affected all versions; fixed in 1.1.0

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/GHSA-mj96-mh85-r574/ (Markdown: https://insights.sbomify.com/GHSA-mj96-mh85-r574/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-mj96-mh85-r574

---
From sbomify Insights: https://insights.sbomify.com/GHSA-mj96-mh85-r574/
Summaries are generated and may contain mistakes; the official description above is the record.