Malicious Code Injection in left_moose_z3n Package - npm Vulnerability
Summary
MAL-2025-105047: Malicious code in left_moose_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The left_moose_z3n package is part of the npm ecosystem, which is widely used for JavaScript package management. This package, like many others, is intended to facilitate the development of applications by providing reusable code. However, it has been identified as part of a malicious campaign that exploits npm's publishing mechanisms to manipulate package metadata and inflate developer reputation scores.
Vulnerability Detail
The vulnerability in the left_moose_z3n package stems from its association with the tea.xyz token reward campaign. This package contains malicious scripts that modify the package.json file by removing private flags, altering version numbers, and generating random package names. The scripts are designed to continuously republish these variants, polluting the npm registry and potentially leading to security risks for developers who unknowingly use these packages.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall left_moose_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, avoid using the left_moose_z3n package and monitor your package-lock.json file for any unauthorized changes. Consider using tools like Vulert to monitor for vulnerabilities in your dependencies.
Conclusion
The left_moose_z3n package poses a significant risk due to its malicious code that alters package metadata. It is crucial for developers to remove this package and monitor their dependencies for vulnerabilities. Utilizing tools like Vulert can help ensure the security of your applications.
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FAQ
The left_moose_z3n package is an npm package that has been identified as part of a malicious campaign aimed at manipulating package metadata.
This vulnerability can lead to unauthorized changes in your package metadata, potentially compromising your application's integrity and security.
If you have installed the left_moose_z3n package, you should uninstall it immediately using 'npm uninstall left_moose_z3n'.
You can use Vulert to monitor your project for open-source vulnerabilities in real-time by analyzing your package-lock.json file.
Yes, you can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without requiring any signup.
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Complete habits, earn Lume Points, and watch your Lume grow as you stay consistent.
