Malicious Code Detected in @zalastax/nolb-react-up Package

@zalastax/nolb-react-up Updated 02 Oct 2025

Summary

14/08/2025
CRITICAL
No i
Critical
Not published

MAL-2025-13838: Malicious code in @zalastax/nolb-react-up (npm). Affected versions are not published. No fix is published. How to fix ↓

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Background

The @zalastax/nolb-react-up package is an npm library designed for React applications, providing utilities for managing load balancers. It is intended to simplify the integration of load balancing features in web applications. However, this package has been found to contain malicious code, posing a significant risk to users who incorporate it into their projects.

Vulnerability Detail

The vulnerability originates from the inclusion of malicious code within the @zalastax/nolb-react-up package. This code can potentially compromise the security of applications using the package, leading to unauthorized access, data breaches, or other malicious activities. The issue affects all versions starting from the initial release, 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 @zalastax/nolb-react-up

If it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.

Tip — Not sure whether your app is affected? Vulert can check the versions your app actually runs. Scan free →

Workaround

As a temporary workaround, consider using alternative packages that provide similar functionality without the security risks. Always ensure to review the package's reputation and community feedback before integrating it into your project.

Conclusion

The discovery of malicious code in the @zalastax/nolb-react-up package highlights the importance of vigilance when using open-source libraries. Users are urged to take immediate action to protect their applications by uninstalling the affected package and exploring alternatives.

See every vulnerability recorded for @zalastax/nolb-react-up →

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FAQ

The malicious code can lead to unauthorized access and potential data breaches.

You can use Vulert to monitor and alert for open-source vulnerabilities in your software. Visit Vulert Scanner to check your application without any signup.

Immediately uninstall the package and consider using alternative solutions until a patched version is released.

Regularly monitor your dependencies using tools like Vulert and keep your packages updated to the latest versions.

Detailed information can be found on the GitHub repository of the malicious package or through vulnerability databases.

How To Fix

This package is malicious. Remove it and rotate any credentials it could have accessed.

npm uninstall @zalastax/nolb-react-up

If it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.

Tip — Not sure whether your app is affected? Vulert can check the versions your app actually runs. Scan free →

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