Malicious Code Injection in ugly_jellyfish_z3n: A Threat to npm Packages
Summary
MAL-2025-97073: Malicious code in ugly_jellyfish_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The package 'ugly_jellyfish_z3n' is part of a broader campaign targeting the npm ecosystem, specifically linked to the tea.xyz token reward initiative. This package, like others in the campaign, is designed to manipulate the npm registry by generating and publishing numerous derivative packages with randomized names. Its primary function is to inflate developer reputation scores in exchange for token rewards, which poses a significant risk to the integrity of the npm registry.
Vulnerability Detail
The vulnerability in 'ugly_jellyfish_z3n' originates from its malicious payload that modifies the package.json file. It removes private flags, alters version numbers, and generates random package names, leading to the continuous republishing of these variants. This behavior not only pollutes the npm registry but also compromises the security of applications relying on this package, potentially leading to further exploitation and misuse of developer credentials.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall ugly_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 measure, you can prevent the installation of this malicious package by using the following command to uninstall it: npm uninstall ugly_jellyfish_z3n. Additionally, consider using npm audit to identify and address vulnerabilities in your project's dependencies.
Conclusion
The 'ugly_jellyfish_z3n' package poses a significant threat to the npm ecosystem due to its malicious behavior aimed at inflating developer reputation scores. It is essential to take immediate action to remove this package and monitor your dependencies for vulnerabilities to maintain the security of your applications.
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FAQ
The impact includes potential exposure of sensitive data, pollution of the npm registry, and compromised application integrity.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time. Check your application against the vulnerability using the Vulert playground at Vulert Scanner.
Immediately uninstall the package using 'npm uninstall ugly_jellyfish_z3n' and review your project's dependencies for any other vulnerabilities.
Yes, tools like Vulert can help monitor your dependencies for vulnerabilities without requiring code access or installation.
It is recommended to check for vulnerabilities regularly, ideally as part of your development workflow, to ensure your application remains secure.
