Malicious Code Execution Vulnerability in booking-eligibility Package
Summary
MAL-2026-17316: Malicious code in booking-eligibility (npm). Affects booking-eligibility versions 1.0.0. No fix is published. How to fix ↓
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Background
The booking-eligibility package is an npm module designed to assist with determining eligibility for various booking scenarios. It is intended for use in applications that require user eligibility checks. However, this package has been found to contain a postinstall lifecycle hook that can execute malicious code, posing a significant risk to users who install it.
Vulnerability Detail
The vulnerability originates from a postinstall lifecycle hook defined in the package.json file of the booking-eligibility package. This hook attempts to run a Windows Script Host command (wscript.exe 4444.vbs) during the installation process. The referenced VBScript file (4444.vbs) is not included in the package, which means it could either fail to execute or, if provided by an attacker through another means, could run malicious code on the installer's machine. This behavior contradicts the package's README, which claims there are 'No installation scripts', creating a misleading impression about the package's functionality. The filename '4444' is reminiscent of a common reverse-shell port, further indicating potential malicious intent.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall booking-eligibilityIf 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 installing the package altogether or use a different package that provides similar functionality without the associated risks. If you must use this package, consider isolating the installation in a controlled environment to mitigate potential risks.
Conclusion
The booking-eligibility package contains a serious vulnerability that can lead to the execution of malicious code during installation. Users are advised to refrain from using this package until a secure version is released and to monitor their systems for any signs of compromise.
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FAQ
The vulnerability involves a postinstall script that can execute malicious code on the user's machine, potentially leading to unauthorized access or data compromise.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time. Visit Vulert Scanner to check if your application is affected without needing to sign up.
If you have installed the package, it is advisable to remove it immediately and monitor your system for any unusual activity.
As of now, there is no patch available. It is recommended to avoid using the package until a secure version is released.
Ignoring this vulnerability could lead to the execution of malicious scripts on your machine, potentially resulting in data loss, unauthorized access, or system compromise.
