Malicious Code Injection in jolly_crow_z3n: A Threat to npm Packages
Summary
MAL-2025-104662: Malicious code in jolly_crow_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
jolly_crow_z3n is an npm package that has been identified as part of a malicious campaign targeting the npm registry. This package is associated with the tea.xyz token reward initiative, which aims to inflate developer reputation scores by flooding the registry with derivative packages. The malicious nature of this package lies in its ability to modify its own metadata and continuously republish variants, thereby polluting the npm ecosystem.
Vulnerability Detail
The vulnerability in jolly_crow_z3n originates from its design to include autopublish scripts that automatically generate and publish derivative packages with randomized names. This behavior not only removes private flags from package.json but also alters version numbers and creates numerous variants that clutter the npm registry. The ramifications of this vulnerability include potential reputation damage for developers, increased difficulty in package management, and the risk of inadvertently using compromised packages.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall jolly_crow_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 monitor your package dependencies using tools like Vulert, which can alert you to open-source vulnerabilities in real-time. You can also utilize the Vulert playground at https://vulert.com/scanner to check if your application is affected by this vulnerability without requiring any signup.
Conclusion
The jolly_crow_z3n package poses a significant threat to the integrity of the npm ecosystem due to its malicious behavior. It is crucial for developers to be aware of such vulnerabilities and take proactive measures to protect their projects. By removing affected packages and utilizing monitoring tools like Vulert, developers can safeguard their applications from potential risks.
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FAQ
jolly_crow_z3n is an npm package that has been identified as part of a malicious campaign to inflate developer reputation scores through the creation of numerous derivative packages.
The vulnerability can lead to the pollution of the npm registry, making it difficult to manage packages and potentially exposing your project to security risks.
You should uninstall the jolly_crow_z3n package immediately and check your project for any dependencies that may be affected.
You can use tools like Vulert to monitor your package-lock.json for vulnerabilities in real-time without needing to access the code or install additional software.
Yes, you can use the Vulert playground at Vulert Scanner to check if your application is affected by vulnerabilities without requiring any signup.
