Critical Malicious Code Vulnerability in @posthog/heartbeat-plugin: Token Theft and Home Directory Destruction
Summary
MAL-2025-191291: Malicious code in @posthog/heartbeat-plugin (npm). Affects @posthog/heartbeat-plugin versions 0.0.8. No fix is published. How to fix ↓
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Background
The @posthog/heartbeat-plugin is an npm package designed to enhance the functionality of PostHog, a product analytics platform. This plugin allows developers to track user interactions and gather insights into product usage. However, it has recently been compromised, exposing users to significant security risks due to malicious code embedded within the package.
Vulnerability Detail
The vulnerability originates from the Sha1-Hulud: The Second Coming NPM worm, which has compromised the @posthog/heartbeat-plugin package. This malicious payload is capable of stealing sensitive tokens and credentials, subsequently publishing them to GitHub. Additionally, the worm can propagate itself to other npm packages owned by the user and may establish persistence through a GitHub action. The malicious code also poses a risk of destroying the user's home directory, leading to potential data loss.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall @posthog/heartbeat-pluginIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a temporary workaround, it is advisable to remove the compromised package from your project until a secure version is released. You can do this by executing the following command: npm uninstall @posthog/heartbeat-plugin. Additionally, monitor your GitHub repositories for any unauthorized changes or actions.
Conclusion
The @posthog/heartbeat-plugin has been compromised by a malicious worm that poses serious security risks, including token theft and home directory destruction. Users are urged to update or uninstall the package immediately and monitor their systems for any unauthorized activity.
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FAQ
The vulnerability involves malicious code that steals tokens and credentials, potentially leading to unauthorized access to user accounts.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time. Visit Vulert Scanner to check your application without needing to sign up.
If you have installed version 0.0.8 of the @posthog/heartbeat-plugin, it is recommended to uninstall it immediately and check for updates or patches.
Yes, the malicious code can propagate to other npm packages owned by the user, increasing the risk of widespread compromise.
Consequences include unauthorized access to sensitive information, potential data loss, and the risk of further propagation of the malicious code.
