Malicious Code Injection in zeroth_leopard_z3n Package
Summary
MAL-2025-92943: Malicious code in zeroth_leopard_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The zeroth_leopard_z3n package is part of the npm ecosystem, often associated with token reward campaigns. It is designed to facilitate the generation and publication of derivative packages. However, this package has been identified as containing malicious code that manipulates its own metadata and publishes variants to inflate developer reputation scores.
Vulnerability Detail
The vulnerability originates from the package's design, which includes scripts that automatically modify the package.json file to remove private flags and change version numbers. It generates random package names and continuously republishes these variants, leading to pollution of the npm registry. This behavior can compromise the integrity of the npm ecosystem and potentially expose users to malicious code.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall zeroth_leopard_z3nIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a temporary measure, you can prevent the installation of this package by adding it to your project's .npmrc file with the following line: 'package-lock=false'. This will help avoid any unintended installations of this malicious package.
Conclusion
The zeroth_leopard_z3n package contains malicious code that poses a significant risk to the integrity of projects using it. Immediate action is required to uninstall the package and prevent further issues. Utilizing tools like Vulert can help monitor for such vulnerabilities in the future.
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FAQ
The zeroth_leopard_z3n package is an npm package associated with token reward campaigns, designed to generate and publish derivative packages.
The malicious code modifies your package.json file, removes private flags, and can lead to the publication of unwanted variants, compromising your project's integrity.
If you have installed the zeroth_leopard_z3n package, you should uninstall it immediately using the command: npm uninstall zeroth_leopard_z3n.
Yes, you can use Vulert, which monitors and alerts for open-source vulnerabilities in your software using just the package-lock.json file. You can check your application for vulnerabilities at the Vulert playground.
There is no patch available for the zeroth_leopard_z3n package, as it is recommended to remove the package entirely from your project.
