Malicious Code Injection in efficient_hare_z3n Package
Summary
MAL-2025-101895: Malicious code in efficient_hare_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The efficient_hare_z3n package is part of the npm ecosystem, often utilized in JavaScript projects for various functionalities. However, it has been identified as part of a malicious campaign that floods the npm registry with derivative packages. These packages are designed to inflate developer reputation scores for token rewards, making them a significant threat to the integrity of the npm ecosystem.
Vulnerability Detail
The vulnerability in the efficient_hare_z3n package stems from its involvement in a malicious campaign that modifies the package.json file to remove private flags, alters version numbers, and generates random package names. This behavior leads to the continuous republishing of variants, which pollutes the npm registry and can compromise the security and reliability of applications that depend on this package.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall efficient_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 measure, you can avoid using the efficient_hare_z3n package and replace it with a trusted alternative. Additionally, you can monitor your package dependencies using tools like Vulert, which alerts you to open-source vulnerabilities in real-time. You can check if your application is affected by this vulnerability using the Vulert playground at https://vulert.com/scanner without any signup.
Conclusion
The efficient_hare_z3n package poses a significant security risk due to its malicious behavior of modifying package files and republishing variants. It is essential to remove this package and monitor your dependencies for vulnerabilities to ensure the integrity of your applications.
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FAQ
The efficient_hare_z3n package is an npm package that has been identified as part of a malicious campaign to inflate developer reputation scores.
This vulnerability can lead to the pollution of the npm registry, potentially compromising the security and reliability of applications that depend on the affected package.
You should remove the efficient_hare_z3n package from your project and monitor for any updates or patches that may be released.
Yes, you can use the Vulert playground at Vulert Scanner to check for vulnerabilities in your application without requiring any signup.
Vulert is a monitoring tool that uses package-lock.json to alert you in real-time about open-source vulnerabilities in your software, helping you maintain secure applications.
