Malicious Code Injection in known_worm_z3n Package
Summary
MAL-2025-95180: Malicious code in known_worm_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The known_worm_z3n package is part of a malicious campaign targeting npm, designed to exploit the npm registry by flooding it with derivative packages. These packages are often associated with token reward schemes that incentivize developers to inflate their reputation scores. The primary functionality of this package is to automate the generation and publication of these derivative packages, which can lead to significant pollution of the npm ecosystem.
Vulnerability Detail
The vulnerability originates from the malicious payload embedded within the known_worm_z3n package. This payload modifies the package.json file by removing private flags, altering version numbers, and generating random package names, primarily themed around Indonesian culture. The continuous republishing of these variants can severely compromise the integrity of the npm registry, leading to potential security risks for developers who unknowingly depend on these packages. The malicious behavior not only affects the reputation of legitimate developers but also poses a risk of dependency confusion and supply chain attacks.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall known_worm_z3nIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a temporary workaround, avoid using the known_worm_z3n package and any packages that may have been derived from it. Regularly audit your project's dependencies using tools like npm audit to identify and mitigate potential vulnerabilities.
Conclusion
The known_worm_z3n package poses a significant risk to the integrity of the npm ecosystem due to its malicious behavior. Developers should take immediate action to remove this package and monitor their projects for any vulnerabilities. Utilizing tools like Vulert can help in maintaining the security of your applications.
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FAQ
The known_worm_z3n package is a malicious npm package designed to automate the creation and publication of derivative packages for the purpose of inflating developer reputation scores.
This vulnerability can lead to the pollution of the npm registry, potentially introducing malicious code into your project and compromising its security.
Immediately uninstall the known_worm_z3n package from your project and audit your dependencies for any other potentially malicious packages.
You can use tools like Vulert, which monitors your package-lock.json file to alert you in real-time for open-source vulnerabilities. You can also check your application against known vulnerabilities using the Vulert playground.
Regularly audit your dependencies, use trusted sources for packages, and consider using automated tools to monitor for vulnerabilities in your projects.
