Malicious Code Detected in fsmfun Package - Security Alert
Summary
MAL-2025-21013: Malicious code in fsmfun (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The fsmfun package is an npm library designed for state machine functionality in JavaScript applications. It offers developers a way to manage complex state transitions in a clean and efficient manner. However, recent findings have revealed that this package contains malicious code, posing significant security risks to applications that utilize it.
Vulnerability Detail
The vulnerability in the fsmfun package stems from the inclusion of malicious code that can compromise the security of applications using this library. This code may allow unauthorized access, data exfiltration, or other harmful actions within the application environment. The issue was introduced in version 0 and affects all subsequent versions, making it critical for developers to address this vulnerability promptly.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall fsmfunIf 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 fsmfun package altogether and implement state management using alternative libraries such as xstate or redux. This will help mitigate the risks associated with the malicious code in fsmfun.
Conclusion
The discovery of malicious code in the fsmfun package poses a serious threat to applications relying on it. Developers are urged to remove this package and consider alternatives to safeguard their applications. Regular monitoring of dependencies using tools like Vulert can help maintain security in the long run.
See every vulnerability recorded for fsmfun →
FAQ
fsmfun is an npm package that provides functionality for managing state machines in JavaScript applications.
The malicious code can lead to unauthorized access and potential data breaches within applications that use the fsmfun package.
You can use Vulert, a tool that monitors and alerts for open-source vulnerabilities. Simply upload your package-lock.json file to check for vulnerabilities in your application.
Currently, there is no patched version available. It is recommended to remove the package and use alternatives until a fix is released.
Utilizing tools like Vulert can help you monitor your dependencies for vulnerabilities in real-time without needing to access the code or install additional software.
