Malicious Code Exploit in bad_bear_z3n Package: npm Vulnerability Overview
Summary
MAL-2025-93343: Malicious code in bad_bear_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The bad_bear_z3n package is part of a series of npm packages that emerged during the tea.xyz token reward campaign. These packages are designed to automate the generation and publication of derivative packages, often with randomized names. The primary functionality of these packages is to inflate developer reputation scores to earn token rewards. However, they are susceptible to malicious exploitation due to their design, which allows for the modification of critical files like package.json.
Vulnerability Detail
The vulnerability in the bad_bear_z3n package stems from its malicious payload that modifies the package.json file. This payload removes private flags, alters version numbers, and generates random package names, leading to the continuous republishing of variants that pollute the npm registry. The origin of this vulnerability is linked to the tea.xyz token reward campaign, which has been associated with numerous malicious packages aimed at manipulating npm's ecosystem.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall bad_bear_z3nIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a workaround, you can manually delete the bad_bear_z3n package from your project by running the following command: npm uninstall bad_bear_z3n. Additionally, consider using tools like Vulert to monitor your package-lock.json for vulnerabilities in real-time.
Conclusion
The bad_bear_z3n package poses a significant risk due to its malicious code that alters essential project files. It is imperative to uninstall this package and monitor your project for vulnerabilities using tools like Vulert to ensure ongoing security.
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FAQ
The bad_bear_z3n package is an npm package associated with a token reward campaign that automates the generation of derivative packages.
The vulnerability can lead to unauthorized modifications of your package.json file, potentially compromising your project's integrity and security.
You should uninstall the bad_bear_z3n package immediately to mitigate any risks associated with the vulnerability.
Currently, there is no patched version available for the bad_bear_z3n package. The best course of action is to remove it from your project.
You can use Vulert, which monitors your package-lock.json for open-source vulnerabilities in real-time without requiring code access or installation.
