Critical Malicious Code Vulnerability in test-brotli-testmetest Package
Summary
MAL-2026-18181: Malicious code in test-brotli-testmetest (npm). Affects test-brotli-testmetest versions 1.0.0. No fix is published. How to fix ↓
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Background
The test-brotli-testmetest package, version 1.0.0, is an npm package that is intended for testing Brotli compression. However, it has been found to contain malicious code that compromises the security of applications using it. This package executes a script during installation that runs an obfuscated loader, which can lead to unauthorized access and data theft.
Vulnerability Detail
The vulnerability originates from the package's install script, which utilizes node-gyp to run an obfuscated JavaScript file (index.js) that decrypts a malicious payload. This payload is a credential stealer that can execute arbitrary code on the user's machine when the package is installed. The use of command expansion in the binding.gyp file allows the attacker to execute the malicious code without the user's knowledge, posing significant risks to data security and application integrity.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall test-brotli-testmetestIf 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 using the test-brotli-testmetest package altogether. If you have already installed it, remove it from your project and monitor your application for any unusual behavior or unauthorized access.
Conclusion
The test-brotli-testmetest package contains a critical vulnerability that allows for the execution of malicious code during installation. It is crucial to remove this package from your project and monitor for any potential security breaches. Utilizing tools like Vulert can help you stay informed about vulnerabilities in your dependencies.
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FAQ
It is an npm package designed for testing Brotli compression, but it has been compromised with malicious code.
The vulnerability allows an attacker to execute malicious code on your machine, potentially leading to data theft and unauthorized access.
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.
Immediately uninstall the test-brotli-testmetest package and monitor your application for any suspicious activity.
Yes, consider using well-known and trusted packages for Brotli compression that do not have known vulnerabilities.
