VYPR

npm · Malicious package advisory

Malware

test-pkg-x0

MAL-2026-6717

Malicious code in test-pkg-x0 (npm)

Details


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_-= Per source details. Do not edit below this line.=-_

## Source: amazon-inspector (0d0014944456f668a25fa484bf7cb5f36a7128d6a585b86d9294d8d49b23049a)
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.

Compromised versions (5)

  • 1.0.4
  • 1.0.3
  • 1.0.0
  • 1.0.2
  • 1.0.1

Any computer that installed or ran a compromised version should be considered fully compromised. Rotate every secret on that machine from a clean environment.