MAL-2025-191402 Malicious code in posthog-js (npm)
Malicious package
Published
MAL-2025-191402 is a malicious package: posthog-js (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-2025-191402/ (Markdown: https://insights.sbomify.com/MAL-2025-191402/index.md)
- Package
- posthog-js
- Registry
- npm
What is MAL-2025-191402?
MAL-2025-191402 is a malicious package in posthog-js, published on 25 Nov 2025.
Official description
The package posthog-js was found to contain malicious code.
This package was compromised by the Sha1-Hulud: The Second Coming NPM worm. The malicious payload steals tokens and credentials and publishes them to GitHub. The worm will propogate itself to NPM packages the user owns and establish persistence is a GitHub action. The package may also destroy the user's home directory.
What should I do about MAL-2025-191402?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.