Malicious Code Injection in underlying_koi_z3n Package - npm Vulnerability
Summary
MAL-2025-97111: Malicious code in underlying_koi_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The underlying_koi_z3n package is part of the npm ecosystem and is associated with the tea.xyz token reward campaign. This package is designed to facilitate token rewards by generating and publishing derivative packages. However, it has been identified as containing malicious code that compromises the integrity of the npm registry.
Vulnerability Detail
The vulnerability stems from the presence of malicious code within the underlying_koi_z3n package. This code is designed to modify the package.json file by removing private flags, altering version numbers, and generating random package names. The malicious payload continuously republishes these variants, leading to pollution of the npm registry and potential exploitation by attackers. The origin of this vulnerability is linked to a broader campaign aimed at inflating developer reputation scores for token rewards.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall underlying_koi_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 remove the underlying_koi_z3n package from your project by executing the following command: npm uninstall underlying_koi_z3n. This will prevent the malicious code from executing until a secure version is available.
Conclusion
The underlying_koi_z3n package has been identified as containing malicious code that poses a significant risk to users and the npm ecosystem. It is crucial to take immediate action by updating or uninstalling the package to safeguard your projects from potential exploitation.
See every vulnerability recorded for underlying_koi_z3n →
FAQ
The underlying_koi_z3n package is an npm package associated with the tea.xyz token reward campaign, designed to generate and publish derivative packages.
The malicious code modifies your package.json file, removes private flags, and continuously republishes variants, which can lead to reputation inflation and registry pollution.
Yes, you can use Vulert, which monitors and alerts for open-source vulnerabilities in your software using just the package-lock.json file. You can check your application for vulnerabilities without any signup at the Vulert playground.
If an immediate update is not possible, consider uninstalling the underlying_koi_z3n package as a temporary measure to mitigate the risk.
Detailed information about this vulnerability can be found in the Open Source Vulnerability database and the npm registry.
