Malicious Code Injection in big_marmoset_z3n: A Threat to npm Ecosystem
Summary
MAL-2025-93378: Malicious code in big_marmoset_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The package big_marmoset_z3n is part of the npm ecosystem, which is widely used for JavaScript package management. This package was identified as part of a malicious campaign that aimed to manipulate the npm registry by publishing numerous derivative packages with altered metadata. The primary functionality of big_marmoset_z3n is to serve as a token reward mechanism, but it has been compromised to serve malicious purposes.
Vulnerability Detail
The vulnerability in big_marmoset_z3n originates from its association with the tea.xyz token reward campaign. It contains scripts designed to automatically generate and publish derivative packages with randomized names, effectively inflating developer reputation scores for token rewards. The malicious payload modifies the package.json file by removing private flags, changing version numbers, and continuously republishing variants, which pollutes the npm registry and can lead to security risks for developers relying on these packages.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall big_marmoset_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 remove the big_marmoset_z3n package from your project to prevent any potential exploitation. Use the following command to uninstall it: 'npm uninstall big_marmoset_z3n'. Additionally, consider using Vulert to monitor your package-lock.json for vulnerabilities in real-time.
Conclusion
The big_marmoset_z3n package poses a significant threat due to its malicious code designed to manipulate the npm registry. It is essential to take immediate action by uninstalling the package and monitoring your project for vulnerabilities. Utilizing tools like Vulert can help maintain the security of your software.
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FAQ
big_marmoset_z3n is an npm package that was part of a malicious campaign to manipulate the npm registry by publishing numerous derivative packages.
The vulnerability can lead to the pollution of the npm registry, potentially affecting the integrity of your project's dependencies and exposing it to security risks.
You should uninstall the package immediately and monitor your project for any potential vulnerabilities using tools like Vulert.
Currently, there is no specific patched version available for big_marmoset_z3n. It is recommended to uninstall the package.
You can use Vulert, which allows you to monitor your package-lock.json for open-source vulnerabilities in real-time without requiring code access or installation.
