Critical Malicious Code Vulnerability in css-overscroll-contain Package
Summary
MAL-2026-17705: Malicious code in css-overscroll-contain (npm). Affects css-overscroll-contain versions 1.0.1 – 1.0.3. No fix is published. How to fix ↓
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Background
The css-overscroll-contain package is an npm utility designed to manage CSS overscroll behavior. It is intended for developers to enhance user experience by controlling how content behaves when it is scrolled. However, this package has been found to contain malicious code that compromises the security of applications using it.
Vulnerability Detail
The vulnerability originates from the package's shipped modules, which execute a self-invoking function immediately upon loading. This function conducts host reconnaissance and steals sensitive credentials by collecting data such as host identity, file descriptors, network information, and Kubernetes service account tokens. The malicious code sends this data to a hardcoded external endpoint, posing significant risks to the security and integrity of affected systems.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall css-overscroll-containIf 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 remove the css-overscroll-contain package from your project until a secure version is available. You can do this by running the following command: npm uninstall css-overscroll-contain.
Conclusion
The css-overscroll-contain package has a critical vulnerability that allows for malicious code execution, leading to potential data theft. It is essential to update or remove the package to protect your application from these risks. Regular monitoring and using tools like Vulert can help maintain the security of your software.
See every vulnerability recorded for css-overscroll-contain →
FAQ
css-overscroll-contain is an npm package designed to manage CSS overscroll behavior for web applications.
The vulnerability allows attackers to perform host reconnaissance and steal sensitive credentials, including tokens and environment variables.
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.
Yes, you can temporarily uninstall the css-overscroll-contain package to mitigate risks until a secure version is released.
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