Malicious Code Injection in Smiling Hare Z3N Package
Summary
MAL-2025-108866: Malicious code in smiling_hare_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The Smiling Hare Z3N package is part of the npm ecosystem, primarily used for various JavaScript functionalities. However, it has been identified as part of a malicious campaign that floods the npm registry with harmful packages. This package, like others involved in the campaign, is designed to inflate developer reputation scores through the automatic generation and publication of derivative packages.
Vulnerability Detail
The vulnerability originates from the Smiling Hare Z3N package being part of a malicious token reward campaign. It contains scripts that modify the package.json file to remove private flags, alter version numbers, and generate random package names. This results in the continuous republishing of variants that pollute the npm registry, potentially leading to security risks for developers and users who inadvertently install these packages.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall smiling_hare_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, avoid using the Smiling Hare Z3N package and any packages that depend on it. Regularly audit your package-lock.json file for any malicious entries. You can also use tools like Vulert to monitor your project for vulnerabilities.
Conclusion
The Smiling Hare Z3N package poses a significant security risk due to its involvement in a malicious campaign. It is crucial for developers to remove this package and monitor their projects for vulnerabilities to ensure the integrity and security of their applications.
See every vulnerability recorded for smiling_hare_z3n →
FAQ
Smiling Hare Z3N is an npm package that has been identified as part of a malicious campaign to inflate developer reputation scores through the automatic generation of harmful packages.
If you have the Smiling Hare Z3N package installed, your project may be at risk of including malicious code that can compromise security and lead to potential data breaches.
You should uninstall the Smiling Hare Z3N package immediately and audit your project for any dependencies that may be affected.
You can use Vulert, which monitors your package-lock.json file for open-source vulnerabilities in real-time. You can check your application using the Vulert playground without any signup.
Regularly audit your dependencies, use tools like Vulert for monitoring, and stay updated on security advisories related to the packages you use.
