# MAL-2026-6717: Malicious code in test-pkg-x0 (npm)


- **Type:** Malicious package
- **Package:** `test-pkg-x0` (npm)
- **Published:** 1 Jul 2026
- **Also known as:** GHSA-45jm-p8g6-hcxf

## What is MAL-2026-6717?

MAL-2026-6717 is a malicious package in test-pkg-x0, published on 1 Jul 2026. 

### Official description

Package declares scripts.postinstall pointing at shim.js, a script that runs unconditionally on npm install. shim.js branches on uname -s (Darwin/MINGW/Linux) and executes OS-native commands on the installer's machine, including launching the Calculator application and opening https://github.com/X3r0Day/BunnyHijack in the installer's default browser via open / cmd /c start / xdg-open. Additionally, package.json registers a `bin` entry named `node` mapped to shim.js. Under package managers that resolve `node` from node_modules/.bin (notably bun), any dependency postinstall that invokes `node` will execute this shim instead of the real Node.js runtime; the declared dependency protoc-gen-grpc-web is used as the trigger. The combined effect is arbitrary command execution on the installer at install time, both directly via the package's own postinstall and indirectly by hijacking the `node` command for sibling dependencies' install scripts. The Calculator launch and browser navigation are a proof-of-concept payload; the underlying execution primitive is fully attacker-controlled.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

## What should I do about MAL-2026-6717?

Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.

## Fix prompt for AI coding agents

```text
MAL-2026-6717 is a malicious package: test-pkg-x0 (npm). Every version was published to cause harm.

Task:
1. Search this repository's dependency manifests and lockfiles for the package, including transitive dependencies.
2. If it is present, remove it, regenerate the lockfile with the project's package manager, and replace whatever it was used for.
3. List any CI runners, developer machines or containers that installed it, so their secrets can be rotated.
4. If the package is not used anywhere, say so and change nothing.

Reference: https://insights.sbomify.com/MAL-2026-6717/ (Markdown: https://insights.sbomify.com/MAL-2026-6717/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-6717

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-6717/
Summaries are generated and may contain mistakes; the official description above is the record.