Malicious Code Injection in yodelling_mule_z3n: A Threat to npm Packages
Summary
MAL-2025-99015: Malicious code in yodelling_mule_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The package yodelling_mule_z3n is part of the npm ecosystem and is associated with the tea.xyz token reward campaign. This campaign has been known to flood the npm registry with packages that contain malicious scripts designed to manipulate package metadata and inflate developer reputation scores. The primary functionality of this package is to serve as a vehicle for these malicious activities, which can lead to severe consequences for developers and users alike.
Vulnerability Detail
The vulnerability in yodelling_mule_z3n originates from its inclusion in a series of malicious packages that modify the package.json file to remove private flags, alter version numbers, and generate random package names. This behavior not only pollutes the npm registry but also poses a risk of unintentional package usage by developers, potentially leading to security breaches and reputation damage. The malicious payload is designed to continuously republish variants, making it difficult to track and mitigate the issue effectively.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall yodelling_mule_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 prevent the installation of this malicious package by using npm's package-lock.json file to lock your dependencies. Additionally, consider using tools like Vulert to monitor your project for vulnerabilities. You can check if your application is affected by this vulnerability using the Vulert playground at https://vulert.com/scanner without any signup.
Conclusion
The yodelling_mule_z3n package poses a significant threat due to its malicious code designed to manipulate npm package metadata. It is crucial for developers to be vigilant, remove affected packages, and utilize monitoring tools like Vulert to safeguard their projects from such vulnerabilities.
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FAQ
yodelling_mule_z3n is an npm package that has been identified as part of a malicious campaign to manipulate package metadata and inflate developer reputation scores.
The vulnerability can lead to unintentional usage of compromised packages, which may introduce security risks and affect the integrity of your project.
You should uninstall the package immediately using the command npm uninstall yodelling_mule_z3n and check your package-lock.json for any lingering references.
Regularly monitor your dependencies using tools like Vulert, which can alert you to vulnerabilities in real-time without requiring access to your code.
Yes, you can use the Vulert playground at Vulert Scanner to check if your application is affected by vulnerabilities without any signup.
