Malicious Code Injection in upper_mouse_z3n: A Threat to npm Package Integrity
Summary
MAL-2025-110209: Malicious code in upper_mouse_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The upper_mouse_z3n package is part of the npm ecosystem, which is widely used for JavaScript package management. This package, like many others, is intended to facilitate the development and deployment of applications by providing reusable code. However, it has been identified as part of a malicious campaign that aims to manipulate the npm registry by generating and publishing derivative packages with harmful scripts.
Vulnerability Detail
The vulnerability in upper_mouse_z3n originates from its association with the tea.xyz token reward campaign, which has been linked to a series of malicious npm packages. The malicious code embedded in this package modifies the package.json file to remove private flags, alters version numbers, and generates random package names, leading to the pollution of the npm registry. This can result in developers inadvertently using compromised packages, potentially exposing their applications to security risks.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall upper_mouse_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 upper_mouse_z3n package and any other packages that may be associated with the tea.xyz campaign. Monitor your project for any dependencies that may introduce similar vulnerabilities.
Conclusion
The upper_mouse_z3n package poses a significant risk due to its malicious code designed to manipulate the npm registry. It is crucial for developers to be vigilant and remove any affected packages while utilizing tools like Vulert to monitor their projects for vulnerabilities.
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FAQ
upper_mouse_z3n is an npm package that has been identified as part of a malicious campaign to manipulate the npm registry.
The malicious code can modify your package.json file, remove private flags, and publish harmful variants, potentially compromising your application's security.
You should uninstall the upper_mouse_z3n package immediately using 'npm uninstall upper_mouse_z3n' and review your other dependencies for security.
You can use tools like Vulert, which monitors your package-lock.json file to alert you in real-time for open-source vulnerabilities.
Yes, you can use the Vulert playground at Vulert Scanner to check for vulnerabilities in your application without requiring any signup.
