Malicious Code Detected in udn_extras: Data Exfiltration Vulnerability
Summary
MAL-2025-6387: Malicious code in udn_extras (npm). Affects udn_extras versions 1.0.0 – 9999.0.0. No fix is published. How to fix ↓
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Background
The udn_extras package is an npm library designed to provide additional functionalities for Node.js applications. However, it has been identified as containing malicious code that executes upon installation. This package can gather sensitive user information and transmit it to an external server, posing significant security risks to users and their applications.
Vulnerability Detail
The vulnerability arises from a postinstall script that executes index.js, which is embedded within the udn_extras package. This script collects sensitive information, including hostname, platform, username, IP address, and environment variables. It then sends this data to an external server (webhook.site) via an HTTPS POST request. This behavior constitutes data exfiltration, which is a serious security concern for users of the package.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall udn_extrasIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a temporary measure, you can prevent the execution of the postinstall script by using the following command when installing the package: npm install udn_extras --ignore-scripts. However, this does not eliminate the risk associated with the package itself.
Conclusion
The udn_extras package has been identified as containing malicious code that poses a significant risk to users by exfiltrating sensitive information. It is crucial to remove this package from your projects and monitor for any updates or patches. Utilizing tools like Vulert can help maintain the security of your applications.
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FAQ
udn_extras is an npm package that provides additional functionalities for Node.js applications but has been found to contain malicious code.
The vulnerability allows the package to exfiltrate sensitive information from your environment, potentially compromising user data and application security.
Immediately uninstall the udn_extras package from your project to mitigate the risk of data exfiltration.
Yes, you can use Vulert, which monitors and alerts in real-time for open-source vulnerabilities using just your package-lock.json file.
You can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without requiring any signup.
