Malicious Code Injection in mammoth_fish_z3n Package
Summary
MAL-2025-95370: Malicious code in mammoth_fish_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The mammoth_fish_z3n package is part of the npm ecosystem, often utilized in JavaScript projects for various functionalities. However, it has been identified as part of a malicious campaign that floods the npm registry with derivative packages. This package is designed to manipulate developer reputation scores through automated publishing scripts, which can lead to significant security risks for users relying on it.
Vulnerability Detail
The vulnerability stems from the malicious code embedded within the mammoth_fish_z3n package. This code modifies the package.json file by removing private flags, altering version numbers, and generating random package names. The intent is to continuously republish these variants, polluting the npm registry and potentially compromising the integrity of projects that depend on this package. The origin of this vulnerability is linked to the tea.xyz token reward campaign, which exploits npm's publishing mechanisms.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall mammoth_fish_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, you can avoid using the mammoth_fish_z3n package and look for alternative packages that provide similar functionality without the associated risks. Additionally, you can monitor your project for any unauthorized changes to the package.json file.
Conclusion
The mammoth_fish_z3n package poses a significant security risk due to its malicious code that alters project files and publishes unauthorized variants. It is crucial for developers to remove this package and monitor their projects for any potential vulnerabilities. Utilizing tools like Vulert can aid in maintaining the security of your software.
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FAQ
The mammoth_fish_z3n package is an npm package that has been identified as part of a malicious campaign to manipulate developer reputation scores.
This vulnerability can lead to unauthorized modifications in your project, potentially compromising its integrity and security.
You should uninstall the mammoth_fish_z3n package immediately and check your project for any unauthorized changes.
Yes, you can use Vulert, which monitors and alerts for open-source vulnerabilities in your software using just package-lock.json.
You can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without any signup.
