Malicious Code Detected in fatkit: A Critical npm Vulnerability
Summary
MAL-2025-20248: Malicious code in fatkit (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The fatkit package is an npm library designed for various utility functions in JavaScript applications. It is widely used for its ease of integration and functionality. However, recent findings have revealed that this package contains malicious code that poses significant security risks to applications utilizing it.
Vulnerability Detail
The vulnerability in the fatkit package arises from the inclusion of malicious code that can compromise the integrity and security of applications. This code can potentially lead to unauthorized access, data breaches, or other malicious activities. The issue was introduced in version 0 and affects all subsequent versions, making it critical for users to take immediate action.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall fatkitIf 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 may consider removing the fatkit package from your project until a secure version is released. You can do this by executing the following command: npm uninstall fatkit. This will help mitigate the risk while you await a fix.
Conclusion
The discovery of malicious code in the fatkit npm package highlights the importance of regularly monitoring and updating dependencies in software projects. Users are urged to take immediate action to secure their applications by updating or removing the affected package.
See every vulnerability recorded for fatkit →
FAQ
Fatkit is an npm package that provides utility functions for JavaScript applications, but it has been found to contain malicious code.
You can check if your application is affected by using Vulert, which monitors vulnerabilities in your package-lock.json file. Visit Vulert Scanner to use the Vulert playground without signing up.
If you are using fatkit, you should immediately update the package to the latest version or remove it from your project until a secure version is released.
Using a vulnerable package can lead to unauthorized access, data breaches, and other malicious activities that can compromise your application's security.
More information about this vulnerability can be found on the GitHub repository for malicious packages, specifically at https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/fatkit/MAL-2025-20248.json.
