Critical Malicious Code Vulnerability in flagstealer Package
Summary
MAL-2025-192798: Malicious code in flagstealer (npm). Affects flagstealer versions 0.30.2 – 0.30.4. No fix is published. How to fix ↓
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Background
The flagstealer package is an npm module designed for various utility functions within JavaScript applications. It is commonly used for managing flags and configurations in projects. However, recent findings have revealed that this package contains malicious code, posing significant security risks to applications that utilize it.
Vulnerability Detail
The vulnerability originates from the flagstealer package, specifically in versions 0.30.2 and 0.30.4. The malicious code embedded within these versions can lead to unauthorized access and potential data breaches. This issue was identified by Amazon Inspector and ReversingLabs, highlighting the importance of scrutinizing third-party packages for security flaws.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall flagstealerIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
If immediate updating is not feasible, consider removing the flagstealer package from your project until a secure version is available. You can do this by executing: npm uninstall flagstealer.
Conclusion
The flagstealer package has been found to contain malicious code in specific versions, posing a serious security threat. It is crucial for developers to update to the latest version or remove the package to safeguard their applications.
See every vulnerability recorded for flagstealer →
FAQ
Flagstealer is an npm package used for managing flags and configurations in JavaScript applications.
The affected versions are 0.30.2 and 0.30.4.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time. Visit Vulert Scanner to check your application without needing to sign up.
As a temporary measure, you can uninstall the flagstealer package from your project.
The vulnerability was identified by Amazon Inspector and ReversingLabs.
