Malicious Code Injection in endless_lemur_z3n: A Threat to npm Packages
Summary
MAL-2025-102091: Malicious code in endless_lemur_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The package 'endless_lemur_z3n' is part of a series of npm packages that emerged during the tea.xyz token reward campaign. These packages are designed to inflate developer reputation scores by automatically generating and publishing derivative packages with randomized names. This behavior not only clutters the npm registry but also poses a significant risk to developers who may unknowingly incorporate these malicious packages into their projects.
Vulnerability Detail
The vulnerability stems from malicious code embedded within the 'endless_lemur_z3n' package. This code modifies the package.json file to remove private flags, alters version numbers, and generates random package names, leading to the continuous republishing of these variants. The primary risk is the pollution of the npm registry, which can mislead developers and compromise the integrity of their applications. The malicious payload is linked to the broader issue of automated scripts that exploit npm for token rewards, making it a significant concern for the open-source community.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall endless_lemur_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 avoid using the 'endless_lemur_z3n' package and instead look for alternative packages that provide similar functionality without the associated risks. Additionally, you can monitor your project's dependencies using tools like Vulert, which can alert you to vulnerabilities in real-time without requiring code access.
Conclusion
The 'endless_lemur_z3n' package poses a significant threat due to its malicious code designed to manipulate npm package metadata and inflate developer reputation scores. It is essential to remove this package from your projects and utilize tools like Vulert to monitor for vulnerabilities effectively.
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FAQ
It is an npm package that is part of a malicious campaign aimed at inflating developer reputation scores through automated publishing of derivative packages.
Incorporating this package can lead to the pollution of your project's dependencies, potentially introducing security risks and misleading information in your package registry.
You should remove the 'endless_lemur_z3n' package from your project and monitor for any updates or patches that may address the issue.
Yes, you can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without needing to sign up.
Vulert monitors and alerts for open-source vulnerabilities in your software using just the package-lock.json file, providing real-time insights into potential risks.
