Malicious Code Injection in guilty_silkworm_z3n Package
Summary
MAL-2025-94777: Malicious code in guilty_silkworm_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The guilty_silkworm_z3n package is part of the npm ecosystem, which is widely used for JavaScript package management. This package has been identified as part of a malicious campaign that aims to exploit the npm registry by flooding it with derivative packages. These packages are designed to inflate developer reputation scores through automated scripts that publish numerous variants of the package with altered names and metadata.
Vulnerability Detail
The vulnerability originates from the guilty_silkworm_z3n package, which contains malicious code that modifies the package.json file to remove private flags, alters version numbers, and generates random package names. This behavior leads to the continuous republishing of these variants, polluting the npm registry and potentially compromising the integrity of the ecosystem. The malicious payload can affect developers by misrepresenting the reputation of packages and introducing security risks.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall guilty_silkworm_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, you can avoid using the guilty_silkworm_z3n package in your projects. Additionally, you can monitor your package dependencies using tools like Vulert, which can alert you to vulnerabilities in real-time without requiring code access or installation. You can check if your application is affected by this vulnerability using the Vulert playground at https://vulert.com/scanner.
Conclusion
The guilty_silkworm_z3n package poses a significant risk due to its malicious code that alters package metadata and floods the npm registry. It is crucial for developers to remove this package and monitor their dependencies for vulnerabilities to maintain the integrity of their projects.
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FAQ
The guilty_silkworm_z3n package is an npm package that has been identified as part of a malicious campaign to exploit the npm registry.
The malicious code modifies your package.json file, removes private flags, and generates random package names, which can lead to reputation inflation and security risks.
Currently, the best way to fix this vulnerability is to remove the guilty_silkworm_z3n package from your project, as there is no patched version available.
You can use tools like Vulert, which monitors your package-lock.json file for vulnerabilities and alerts you in real-time without requiring code access.
You can check if your application is affected by this vulnerability using the Vulert playground at Vulert Scanner.
