Malicious Code Injection in then_fly_z3n Package - npm Vulnerability
Summary
MAL-2025-96981: Malicious code in then_fly_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The then_fly_z3n package is part of the npm ecosystem, often used in JavaScript projects. It has been identified as part of a larger campaign that aims to exploit the npm registry by flooding it with malicious packages. These packages typically contain scripts that manipulate package metadata and publish numerous variants to inflate developer reputation scores for token rewards.
Vulnerability Detail
The vulnerability in the then_fly_z3n package originates from its association with the tea.xyz token reward campaign. It includes malicious code that 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, which pollutes the npm registry and can compromise the integrity of projects relying on this package.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall then_fly_z3nIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a workaround, you can manually remove the then_fly_z3n package from your project by executing the following command in your terminal: npm uninstall then_fly_z3n. Additionally, consider using alternative packages that do not have known vulnerabilities.
Conclusion
The then_fly_z3n package poses a significant risk due to its malicious code that alters package metadata and floods the npm registry. It is essential to remove this package from your projects and monitor for any vulnerabilities to maintain the integrity of your applications.
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FAQ
The then_fly_z3n package is an npm package that has been identified as part of a malicious campaign to exploit the npm registry.
This vulnerability can compromise the integrity of your project by introducing malicious code that alters package metadata and floods the npm registry.
If you have installed the then_fly_z3n package, it is crucial to uninstall it immediately and monitor your project for any unusual behavior.
Yes, you can use tools like Vulert, which monitors and alerts for open-source vulnerabilities in your software using just the package-lock.json file.
You can check if your application is affected by this vulnerability using the Vulert playground at Vulert Scanner without any signup.
