Malicious Code Injection in medieval_yak_z3n: A Threat to npm Packages
Summary
MAL-2025-105768: Malicious code in medieval_yak_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The package 'medieval_yak_z3n' 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 for token rewards, making them a significant threat to the integrity of the npm ecosystem.
Vulnerability Detail
The vulnerability in 'medieval_yak_z3n' originates from its involvement in the tea.xyz token reward campaign. It contains malicious scripts that modify the package.json file by removing private flags, altering version numbers, and generating random package names. This behavior leads to the continuous republishing of these variants, which pollutes the npm registry and can compromise the security of applications relying on these packages. The malicious payload can potentially allow unauthorized access to sensitive data and disrupt the normal functioning of dependent applications.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall medieval_yak_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 avoid using the 'medieval_yak_z3n' package and replace it with a trusted alternative. Always verify the integrity of packages before installation.
Conclusion
The 'medieval_yak_z3n' package poses a significant threat due to its malicious code that alters package.json files and floods the npm registry. It is crucial to remove this package from your projects and utilize trusted alternatives. Regular monitoring for vulnerabilities using tools like Vulert can help maintain the security of your applications.
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FAQ
The vulnerability involves malicious code that modifies package.json files and floods the npm registry with derivative packages.
You can use the Vulert platform to monitor and alert for open-source vulnerabilities in your software. Visit Vulert Scanner to check if your application is affected without any signup.
You should uninstall the package immediately using 'npm uninstall medieval_yak_z3n' and replace it with a trusted alternative.
The malicious code can lead to unauthorized access to sensitive data and disrupt the normal functioning of applications that depend on the compromised package.
There is no patch available for this package. The best course of action is to uninstall it and avoid using it.
