Malicious Code Vulnerability in @client-web-next/ab-tests Package
Summary
MAL-2026-16494: Malicious code in @client-web-next/ab-tests (npm). Affects @client-web-next/ab-tests versions 0.0.1. No fix is published. How to fix ↓
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Background
The @client-web-next/ab-tests package is an npm library designed for A/B testing in web applications. It allows developers to implement experiments to optimize user experience and engagement. However, this package has been identified as containing malicious code, which poses significant security risks to applications that utilize it.
Vulnerability Detail
The vulnerability stems from the presence of malicious code within the @client-web-next/ab-tests package, specifically in version 0.0.1. This code can potentially compromise the integrity of applications that depend on this package, leading to unauthorized access, data breaches, or other malicious activities. The issue was reported by ReversingLabs and is cataloged under the ID MAL-2026-16494.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall @client-web-next/ab-testsIf 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 @client-web-next/ab-tests package from your project until a secure version is released. Use the following command to uninstall it: npm uninstall @client-web-next/ab-tests.
Conclusion
The @client-web-next/ab-tests package has been identified as containing malicious code, posing a significant risk to applications that utilize it. It is crucial to update or remove the package to protect your application from potential threats. Utilize tools like Vulert for ongoing monitoring of vulnerabilities in your dependencies.
See every vulnerability recorded for @client-web-next/ab-tests →
FAQ
The malicious code can compromise application security, leading to unauthorized access or data breaches.
You can use Vulert's playground at Vulert Scanner to check if your application is affected without needing to sign up.
If an immediate update is not possible, consider removing the package as a temporary measure to mitigate risks.
The vulnerability was reported by ReversingLabs, a cybersecurity firm specializing in threat detection.
Yes, Vulert can monitor and alert you in real-time for open-source vulnerabilities in your software using just the package-lock.json file.
