Malicious Code Execution in a11y-tabindex-manager Package
Summary
MAL-2026-17501: Malicious code in a11y-tabindex-manager (npm). Affects a11y-tabindex-manager versions 1.0.0. No fix is published. How to fix ↓
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Background
The a11y-tabindex-manager is an npm package designed to assist with accessibility features in web applications. It is intended to manage tabindex attributes to improve user experience for individuals relying on assistive technologies. However, a serious vulnerability has been discovered that compromises the integrity of the package, allowing for malicious code execution.
Vulnerability Detail
The vulnerability originates from the inclusion of a file named thunderboltRegistry.js, which executes an Immediately Invoked Function Expression (IIFE) upon module loading. This IIFE runs a series of local shell commands that gather sensitive information such as user identity, network configuration, and environment variables. The output of these commands is sent over plain HTTP to a hardcoded endpoint, exposing the user to potential data theft and unauthorized access. The method of acquiring the child_process module through evasion techniques further complicates detection and mitigation efforts.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall a11y-tabindex-managerIf 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 a11y-tabindex-manager package from your project by executing:
npm uninstall a11y-tabindex-manager
This will prevent the execution of the malicious code until a fix is provided.
Conclusion
The a11y-tabindex-manager package has a critical vulnerability that allows for the execution of malicious code, compromising user data and security. It is essential to update or remove the package to protect your application from potential threats.
See every vulnerability recorded for a11y-tabindex-manager →
FAQ
It is an npm package designed to manage tabindex attributes for accessibility in web applications.
The vulnerability allows malicious code to execute, potentially exposing sensitive information and compromising user security.
Yes, you can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time. You can check your application using the Vulert playground without any signup.
If an update is not possible, you should uninstall the package to mitigate the risk until a secure version is available.
Detailed information can be found in the vulnerability report and on platforms like Vulert that track open-source vulnerabilities.
