Malicious Code Injection in adjacent_lemming_z3n Package
Summary
MAL-2025-93131: Malicious code in adjacent_lemming_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The adjacent_lemming_z3n package 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 exploit npm's publishing capabilities. It is designed to automatically generate and publish derivative packages with randomized names, thereby inflating developer reputation scores for token rewards. The package's functionality is compromised by its malicious intent, making it a significant risk for developers who may unknowingly include it in their projects.
Vulnerability Detail
The vulnerability stems from the package's design, which includes autopublish scripts that modify the package.json file to remove private flags, change version numbers, and generate random package names. This behavior leads to the continuous republishing of variants, polluting the npm registry and potentially compromising the integrity of other packages. The malicious payload can affect developers by introducing unwanted dependencies and altering project configurations, which can lead to security breaches and loss of control over the software development process.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall adjacent_lemming_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 prevent the installation of this package by using npm's package-lock.json file to monitor dependencies. Ensure that your project does not include adjacent_lemming_z3n or any of its derivatives. You can also use tools like Vulert to monitor your project for vulnerabilities in real-time without needing to access the code directly. You can check if your application is affected by this vulnerability using the Vulert playground at https://vulert.com/scanner.
Conclusion
The adjacent_lemming_z3n package poses a significant risk due to its malicious code that alters project configurations and publishes unwanted variants. Developers are advised to remove this package and monitor their projects for vulnerabilities using tools like Vulert. Taking proactive steps can help maintain the integrity and security of software projects.
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FAQ
The adjacent_lemming_z3n package is an npm package that has been identified as part of a malicious campaign to exploit npm's publishing capabilities.
This vulnerability can introduce unwanted dependencies, alter project configurations, and compromise the integrity of your software development process.
You should uninstall the adjacent_lemming_z3n package using the command npm uninstall adjacent_lemming_z3n and check your package-lock.json file for any references.
Yes, you can use Vulert to monitor your project for open-source vulnerabilities in real-time by analyzing your package-lock.json file.
Yes, you can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without any signup.
