Malicious Code Injection in circular_weasel_z3n: A Threat to npm Ecosystem
Summary
MAL-2025-93559: Malicious code in circular_weasel_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
circular_weasel_z3n is an npm package that has been identified as part of a malicious campaign targeting the npm registry. This package, like others in the same campaign, is designed to manipulate the npm ecosystem by generating and publishing derivative packages with randomized names. Its primary function is to inflate developer reputation scores for token rewards associated with the tea protocol. The presence of this package poses a significant risk to developers and users relying on npm for package management.
Vulnerability Detail
The vulnerability in circular_weasel_z3n stems from its malicious payload, which modifies the package.json file to remove private flags, alters version numbers, and generates random package names. This behavior leads to the continuous republishing of variants, effectively polluting the npm registry. The origin of this vulnerability is linked to the tea.xyz token reward campaign, which exploits npm's publishing mechanisms to create a flood of derivative packages, thereby compromising the integrity of the ecosystem.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall circular_weasel_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 circular_weasel_z3n by using the following command to block it: npm install --no-save circular_weasel_z3n. However, the best practice is to remove the package entirely.
Conclusion
The circular_weasel_z3n package poses a significant threat to the npm ecosystem due to its malicious behavior. It is crucial for developers to be aware of such vulnerabilities and take immediate action to remove affected packages. Utilizing tools like Vulert can help in monitoring and managing open-source vulnerabilities effectively.
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FAQ
circular_weasel_z3n is an npm package identified as part of a malicious campaign that manipulates the npm registry.
The vulnerability can lead to the pollution of the npm registry and may compromise the integrity of your project's dependencies.
You should uninstall the circular_weasel_z3n package immediately and ensure your project is not relying on it.
Yes, you can use tools like Vulert, which monitors your package-lock.json for open-source vulnerabilities in real-time.
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