Malicious Code in expected_emu_z3n: A Threat to npm Packages
Summary
MAL-2025-102363: Malicious code in expected_emu_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The package 'expected_emu_z3n' is part of the npm ecosystem, which is widely used for JavaScript package management. This package has been identified as part of a malicious campaign that aims to inflate developer reputation scores through the generation of numerous derivative packages. These packages often contain scripts designed to manipulate the npm registry and compromise the integrity of the ecosystem.
Vulnerability Detail
The vulnerability in 'expected_emu_z3n' stems from its association with a malicious campaign 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, polluting the npm registry and potentially compromising other packages. The origin of this issue is linked to the tea.xyz token reward campaign, which exploits npm for malicious purposes.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall expected_emu_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 'expected_emu_z3n' package altogether. If it is already in use, consider removing it from your dependencies and replacing it with a reputable alternative.
Conclusion
The 'expected_emu_z3n' package poses a significant threat due to its malicious code designed to manipulate the npm registry. It is crucial to remove this package from your dependencies and monitor for any updates or patches. Utilizing tools like Vulert can help you stay informed about vulnerabilities in your application.
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FAQ
The malicious code can lead to the pollution of the npm registry, affecting the integrity of other packages and potentially compromising your application.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time. Visit Vulert Scanner to check your application without requiring any signup.
You should remove the package from your project and consider replacing it with a safer alternative.
Currently, there is no patched version available. It is recommended to remove the package until a secure version is released.
Vulert uses your package-lock.json file to monitor and alert you in real-time for any open-source vulnerabilities, ensuring your application remains secure.
