Malicious Code in grieving_jellyfish_z3n: A Threat to npm Packages
Summary
MAL-2025-94750: Malicious code in grieving_jellyfish_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The package 'grieving_jellyfish_z3n' is part of a series of npm packages that emerged during the tea.xyz token reward campaign. These packages are designed to inflate developer reputation scores by automatically generating and publishing derivative packages with randomized names. This behavior not only clutters the npm registry but also poses significant security risks to developers and users alike.
Vulnerability Detail
The vulnerability in 'grieving_jellyfish_z3n' originates from its malicious code, which modifies the package.json file to remove private flags and alters version numbers. It generates random package names, often themed around Indonesian culture, and continuously republishes these variants to pollute the npm registry. This behavior can lead to unauthorized access, reputation damage for developers, and potential exploitation of users who unknowingly install these malicious packages.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall grieving_jellyfish_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 prevent the installation of this malicious package by using npm's package-lock.json to monitor dependencies. Ensure that your project does not include 'grieving_jellyfish_z3n' in its dependencies. You can also use the following command to uninstall it: npm uninstall grieving_jellyfish_z3n.
Conclusion
The 'grieving_jellyfish_z3n' package poses a significant security threat due to its malicious code designed to manipulate npm packages. It is essential for developers to be vigilant, remove such packages, and utilize tools like Vulert to monitor for vulnerabilities in their projects.
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FAQ
'grieving_jellyfish_z3n' is an npm package that is part of a malicious campaign to inflate developer reputation scores by flooding the npm registry with derivative packages.
The vulnerability can lead to unauthorized modifications of your project's package.json file, potentially exposing your project to security risks and reputation damage.
You should immediately uninstall 'grieving_jellyfish_z3n' from your project and check for any unauthorized changes to your package.json file.
Yes, you can use tools like Vulert, which monitors your package-lock.json for open-source vulnerabilities in real-time without requiring code access or installation.
You can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without needing to sign up.
