Malicious Code Injection in big_eel_z3n: A Threat to npm Ecosystem
Summary
MAL-2025-99966: Malicious code in big_eel_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The package big_eel_z3n is part of the npm ecosystem and is associated with the tea.xyz token reward campaign. It is designed to manipulate the npm registry by generating and publishing derivative packages with randomized names. This behavior is intended to inflate developer reputation scores for token rewards, making it a significant concern for developers relying on npm for package management.
Vulnerability Detail
The vulnerability in big_eel_z3n stems from its malicious payload, which modifies the package.json file to remove private flags, alters version numbers, and generates random package names. This allows the package to continuously republish variants, polluting the npm registry and potentially compromising the integrity of other packages. The origin of this issue is linked to the tea.xyz token reward campaign, which exploits npm's publishing mechanisms.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall big_eel_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 prevent the installation of this malicious package by using npm's package-lock.json to monitor dependencies. Additionally, consider using tools like Vulert to check for vulnerabilities in your project. You can access the Vulert playground at https://vulert.com/scanner to analyze your application without any signup.
Conclusion
The big_eel_z3n package poses a significant risk to the npm ecosystem due to its malicious behavior of manipulating package metadata and republishing variants. It is crucial for developers to remove this package and monitor their projects for vulnerabilities using tools like Vulert.
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FAQ
big_eel_z3n is an npm package associated with the tea.xyz token reward campaign, which aims to manipulate the npm registry.
The vulnerability can lead to the pollution of the npm registry, potentially compromising the integrity of your project's dependencies.
You should uninstall the package immediately using the command: npm uninstall big_eel_z3n.
Yes, tools like Vulert can help monitor and alert you in real-time for open-source vulnerabilities in your software.
You can use the Vulert playground at Vulert Scanner to check your application for vulnerabilities without needing to sign up.
