Malicious Code Injection in usual_sloth_z3n Package
Summary
MAL-2025-97215: Malicious code in usual_sloth_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The usual_sloth_z3n package is part of the npm ecosystem, which is widely used for JavaScript development. This package, like many others, is intended to facilitate various functionalities within applications. However, it has been identified as part of a malicious campaign that aims to inflate developer reputation scores through the creation of derivative packages. This vulnerability exposes users to potential security risks as it modifies essential files and repackages them with harmful intent.
Vulnerability Detail
The vulnerability in the usual_sloth_z3n package originates from its association with the tea.xyz token reward campaign, which has been linked to the distribution of malicious npm packages. The malicious code embedded within this package is designed to alter the package.json file by removing private flags, changing version numbers, and generating random package names. This results in the continuous republishing of these variants, which pollutes the npm registry and can lead to unintended consequences for developers relying on these packages. The ramifications include compromised application integrity and potential exploitation of the affected systems.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall usual_sloth_z3nIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a temporary workaround, consider removing the usual_sloth_z3n package from your project until a secure version is released. You can do this by executing the following command: npm uninstall usual_sloth_z3n. Additionally, monitor your package-lock.json file for any unauthorized changes.
Conclusion
The usual_sloth_z3n package has been identified as containing malicious code that poses significant risks to applications using it. Developers are advised to take immediate action to update or remove the package and to utilize tools like Vulert for ongoing monitoring of vulnerabilities in their projects.
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FAQ
The usual_sloth_z3n package is an npm package used in JavaScript development, but it has been identified as part of a malicious campaign.
This vulnerability can compromise the integrity of your application by modifying essential files and republishing malicious variants.
You should immediately update or uninstall the package until a secure version is available.
You can use tools like Vulert, which monitors your package-lock.json for vulnerabilities in real-time without requiring code access.
You can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without signing up.
