Malicious Code Vulnerability in cookie-mapper: A Threat to npm Users
Summary
MAL-2025-192728: Malicious code in cookie-mapper (npm). Affects cookie-mapper versions 1.1.0. No fix is published. How to fix ↓
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Background
cookie-mapper is an npm package designed to facilitate the mapping of cookies in web applications. It is commonly used by developers to manage cookie data efficiently. However, this package has been identified as containing malicious code, which poses significant risks to users who rely on it for secure cookie management.
Vulnerability Detail
The vulnerability stems from the presence of malicious code within the cookie-mapper package, specifically in version 1.1.0. This code can potentially compromise user data, allowing attackers to manipulate cookie information or execute unauthorized actions within applications that utilize this package. The malicious code was identified by ReversingLabs and is documented in the Open Source Vulnerability database.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall cookie-mapperIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a temporary workaround, users can remove the cookie-mapper package from their project until a secure version is released. This can be done with the following command: npm uninstall cookie-mapper. Consider using alternative packages that provide similar functionality without the associated risks.
Conclusion
The discovery of malicious code in the cookie-mapper package highlights the importance of vigilance in managing dependencies in software projects. Users are urged to update or remove the affected package to safeguard their applications from potential threats.
See every vulnerability recorded for cookie-mapper →
FAQ
The malicious code can manipulate cookie data and potentially allow unauthorized access to user sessions.
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If an immediate update is not possible, consider removing the package and using an alternative until a secure version is available.
The vulnerability was discovered by ReversingLabs, which specializes in identifying malicious packages in open-source ecosystems.
Currently, version 1.1.0 is known to be affected. Always check the package repository for updates on other potentially affected versions.
