Malicious Code Injection in yelping_sheep_z3n Package
Summary
MAL-2025-111292: Malicious code in yelping_sheep_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Background
The yelping_sheep_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. However, it has been identified as containing malicious code that compromises its integrity and the security of the npm registry.
Vulnerability Detail
The vulnerability in the yelping_sheep_z3n package 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 is intended to flood the npm registry with variants, thereby polluting it and potentially leading to security risks for developers who may unknowingly use these compromised packages. The origin of this issue is linked to the tea.xyz token reward campaign, which has been associated with various malicious npm packages.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall yelping_sheep_z3nIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
Tip — Not sure whether your app is affected? Vulert can check the versions your app actually runs. Scan free →
Workaround
As a temporary workaround, you can avoid using the yelping_sheep_z3n package and instead look for alternative packages that provide similar functionality without the associated risks. Additionally, you can monitor your package-lock.json file for any unauthorized changes.
Conclusion
The yelping_sheep_z3n package has been identified as containing malicious code that poses significant risks to developers and their applications. It is crucial to remove this package and monitor your project for vulnerabilities to maintain security.
See every vulnerability recorded for yelping_sheep_z3n →
FAQ
The yelping_sheep_z3n package is an npm package involved in the tea.xyz token reward campaign, designed to automate the generation and publication of derivative packages.
The vulnerability can lead to the introduction of malicious code into your application, potentially compromising its security and integrity.
You should remove the yelping_sheep_z3n package from your project immediately and monitor your application for any unusual behavior.
Yes, you can use Vulert, which monitors your package-lock.json file for open-source vulnerabilities in real-time. You can check your application for vulnerabilities using the Vulert playground without any signup.
Regularly update your dependencies, monitor for vulnerabilities using tools like Vulert, and review your package-lock.json file for any unauthorized changes.
