Malicious Code Injection in well_monkey_z3n Package - npm Vulnerability
Summary
MAL-2025-92190: Malicious code in well_monkey_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The well_monkey_z3n package is part of the npm ecosystem, which is widely used for JavaScript package management. This package is suspected to be involved in a malicious campaign that aims to inflate developer reputation scores through the creation and publication of numerous derivative packages. The malicious behavior includes modifying package metadata and republishing variants to pollute the npm registry.
Vulnerability Detail
The vulnerability originates from the well_monkey_z3n package, which is part of a broader malicious campaign targeting npm. The malicious code is designed to alter the package.json file by removing private flags, changing version numbers, and generating random package names. This behavior can lead to the proliferation of untrustworthy packages in the npm registry, potentially compromising the integrity of applications that depend on these packages.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall well_monkey_z3nIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a workaround, you can avoid using the well_monkey_z3n package and replace it with a similar, trusted package that does not exhibit malicious behavior. Additionally, consider using tools like Vulert to monitor your dependencies for vulnerabilities.
Conclusion
The well_monkey_z3n package has been identified as a source of malicious code that can compromise the integrity of applications using it. It is crucial to uninstall this package and monitor your dependencies for vulnerabilities using tools like Vulert to maintain the security of your software.
See every vulnerability recorded for well_monkey_z3n →
FAQ
The well_monkey_z3n package is an npm package that has been identified as part of a malicious campaign to inflate developer reputation scores.
The malicious code modifies package metadata and can lead to the publication of untrustworthy packages, potentially compromising your application's security.
If you have installed the well_monkey_z3n package, you should uninstall it immediately using 'npm uninstall well_monkey_z3n'.
You can use Vulert, which monitors your package-lock.json file to alert you in real-time for open-source vulnerabilities without requiring code access.
Yes, you can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without any signup.
