Malicious Code Injection in cruel_bison_z3n: A Threat to npm Users
Summary
MAL-2025-101118: Malicious code in cruel_bison_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The package 'cruel_bison_z3n' is part of a series of malicious npm packages associated with the tea.xyz token reward campaign. These packages are designed to inflate developer reputation scores by automatically generating and publishing numerous derivative packages with randomized names. The malicious nature of this package lies in its ability to modify critical files and republish itself, thereby polluting the npm registry.
Vulnerability Detail
The vulnerability in 'cruel_bison_z3n' originates from its malicious payload, which alters the package.json file to remove private flags, changes version numbers, and generates random names for derivative packages. This behavior can lead to significant security risks, including unauthorized access to sensitive information and the potential for further exploitation within the npm ecosystem. The package's design is intended to disrupt the integrity of the npm registry by flooding it with harmful variants.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall cruel_bison_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, you can prevent the installation of this malicious package by using npm's package-lock.json to monitor dependencies. Ensure that your package-lock.json does not include 'cruel_bison_z3n'. You can also use the following command to audit your dependencies: 'npm audit'.
Conclusion
The 'cruel_bison_z3n' package poses a significant threat to npm users due to its malicious behavior of altering package files and flooding the npm registry. It is essential to take immediate action to remove this package and monitor your dependencies for any vulnerabilities. Utilizing tools like Vulert can help safeguard your projects against such threats.
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FAQ
'cruel_bison_z3n' is a malicious npm package designed to inflate developer reputation scores through the automatic generation and publication of derivative packages.
This vulnerability can compromise your project's integrity by modifying critical files and flooding the npm registry with malicious packages, potentially leading to security breaches.
Immediately uninstall 'cruel_bison_z3n' using 'npm uninstall cruel_bison_z3n' and audit your project dependencies for any other malicious packages.
Yes, you can use tools like Vulert, which monitors your package-lock.json for open-source vulnerabilities in real-time without requiring code access or installation.
You can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without any signup.
