Malicious Code Injection in upset_crow_z3n Package - npm Vulnerability
Summary
MAL-2025-110214: Malicious code in upset_crow_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The upset_crow_z3n package is part of the npm ecosystem and is associated with the tea.xyz token reward campaign. This package is designed to facilitate the automatic generation and publication of derivative packages, which can inflate developer reputation scores for token rewards. However, it has been identified as containing malicious code that compromises its integrity and the integrity of the npm registry.
Vulnerability Detail
The vulnerability in the upset_crow_z3n package originates 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, polluting the npm registry and potentially affecting other developers and users relying on legitimate packages. The malicious code is part of a broader scheme to exploit the npm ecosystem for token rewards.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall upset_crow_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 monitor your dependencies using tools like Vulert, which allows you to check for vulnerabilities in your package-lock.json file without requiring code access or installation. You can use the Vulert playground at https://vulert.com/scanner to see if your application is affected by this vulnerability.
Conclusion
The upset_crow_z3n package poses a significant risk due to its malicious code, which alters package metadata and pollutes the npm registry. It is essential to remove this package from your project and monitor your dependencies for vulnerabilities using tools like Vulert.
See every vulnerability recorded for upset_crow_z3n →
FAQ
The upset_crow_z3n package is an npm package associated with the tea.xyz token reward campaign, designed to automatically generate and publish derivative packages.
The malicious code modifies your package.json file, removes private flags, and generates random package names, which can lead to pollution of the npm registry and affect other developers.
Currently, there is no patched version available for the upset_crow_z3n package. The recommended action is to uninstall the package.
You can use Vulert to monitor your package-lock.json file for open-source vulnerabilities in real-time without requiring code access or installation.
If you have installed the upset_crow_z3n package, you should uninstall it immediately using the command: npm uninstall upset_crow_z3n.
