Malicious Code Injection in sheer_butterfly_z3n: A Threat to npm Ecosystem
Summary
MAL-2025-96561: Malicious code in sheer_butterfly_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The package 'sheer_butterfly_z3n' is part of a broader initiative associated with the tea.xyz token reward campaign. This npm package is designed to facilitate the automatic generation and publication of derivative packages, which can inflate developer reputation scores. However, it has been identified as containing malicious scripts that compromise the integrity of the npm registry.
Vulnerability Detail
The vulnerability in 'sheer_butterfly_z3n' originates from malicious code that modifies the package.json file to remove private flags and alters version numbers. It generates random package names, often themed around Indonesian culture, and continuously republishes these variants. This behavior not only pollutes the npm registry but also poses a risk to developers who may unknowingly use these compromised packages, potentially leading to security breaches and loss of trust in the ecosystem.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall sheer_butterfly_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 'sheer_butterfly_z3n' package and monitor your project for any dependencies that may indirectly include it. Additionally, consider using tools like Vulert to monitor your package-lock.json for vulnerabilities in real-time.
Conclusion
The 'sheer_butterfly_z3n' package poses a significant threat due to its malicious code that compromises the npm ecosystem. Developers are advised to remove this package and monitor their projects for similar vulnerabilities to maintain security and integrity.
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FAQ
'sheer_butterfly_z3n' is an npm package associated with a token reward campaign that has been identified to contain malicious code.
The malicious code modifies your package.json file, removes private flags, and can lead to the publication of compromised packages, potentially affecting your project's security.
You can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without needing to sign up.
If you have installed 'sheer_butterfly_z3n', you should uninstall it immediately using 'npm uninstall sheer_butterfly_z3n' to mitigate any risks.
Regularly update your dependencies, use trusted packages, and utilize tools like Vulert to monitor your projects for vulnerabilities.
