Malicious Code Injection in tight_sloth_z3n: A Threat to npm Packages
Summary
MAL-2025-109699: Malicious code in tight_sloth_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
tight_sloth_z3n is an npm package that has been identified as part of a malicious campaign targeting the npm registry. This package is associated with the tea.xyz token reward initiative, which aims to inflate developer reputation scores by flooding the registry with derivative packages. The malicious nature of this package lies in its ability to manipulate package metadata and publish numerous variants, thereby polluting the npm ecosystem.
Vulnerability Detail
The vulnerability in tight_sloth_z3n originates from its design to execute autopublish scripts that modify the package.json file. This includes removing private flags, altering version numbers, and generating random package names, which can lead to a significant increase in the number of malicious packages in the npm registry. The ramifications include potential security risks for developers who unknowingly install these packages, as they may contain harmful code or lead to reputation damage for legitimate developers.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall tight_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, you can avoid using the tight_sloth_z3n package and monitor your project's dependencies for any signs of malicious activity. Implementing a package-lock.json file can help maintain the integrity of your dependencies.
Conclusion
The tight_sloth_z3n package poses a significant threat to the npm ecosystem due to its malicious code designed to manipulate package metadata. It is crucial for developers to be vigilant, remove any affected packages, and utilize tools like Vulert to monitor their projects for vulnerabilities.
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FAQ
tight_sloth_z3n is an npm package identified as part of a malicious campaign that modifies package metadata to inflate developer reputation scores.
The vulnerability can lead to the installation of malicious packages, which may contain harmful code, potentially compromising your project's security.
You should uninstall the package immediately using 'npm uninstall tight_sloth_z3n' and review your project's dependencies for any other vulnerabilities.
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.
Yes, you can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without any signup.
