Malicious Code Injection in impressed_lion_z3n: A Threat to npm Packages
Summary
MAL-2025-94957: Malicious code in impressed_lion_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The package 'impressed_lion_z3n' is part of the npm ecosystem, which is widely used for JavaScript package management. This package is associated with the tea.xyz token reward campaign, which has been known to flood the npm registry with malicious packages. These packages often include scripts that automatically generate and publish derivative packages, compromising the integrity of the npm ecosystem.
Vulnerability Detail
The vulnerability in 'impressed_lion_z3n' stems from its malicious code that modifies the package.json file to remove private flags and change version numbers. It generates random package names, often themed around Indonesian culture, and continuously republishes these variants to pollute the npm registry. This behavior not only inflates developer reputation scores for token rewards but also poses a significant risk by potentially introducing harmful code into projects that depend on these packages.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall impressed_lion_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, avoid using the 'impressed_lion_z3n' package and consider using alternative packages that provide similar functionality without the associated risks. You can also implement a script to monitor your package.json for unauthorized changes.
Conclusion
The 'impressed_lion_z3n' package poses a significant risk due to its malicious code designed to manipulate npm packages. It is essential to remove this package from your projects and monitor your dependencies for similar vulnerabilities. Utilizing tools like Vulert can help maintain the security of your applications.
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FAQ
The main issue is that it contains malicious code that modifies package.json files and republishes variants to pollute the npm registry.
You can use tools like Vulert, which monitors your package-lock.json for vulnerabilities. Visit Vulert Scanner to check your application without needing to sign up.
Using this package can lead to the introduction of harmful code into your project, potentially compromising security and functionality.
Regularly audit your dependencies and use tools like Vulert to monitor for vulnerabilities in real-time.
Remove the package immediately and check your project for any unauthorized changes or dependencies that may have been introduced.
