Malicious Code Injection in melted_halibut_z3n Package - npm Vulnerability
Summary
MAL-2025-95441: Malicious code in melted_halibut_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
The melted_halibut_z3n package is part of the npm ecosystem and appears to be linked to a token reward campaign that has been flooding the npm registry. This package is designed to manipulate developer reputation scores by automatically generating and publishing derivative packages with randomized names. Its functionality is primarily centered around creating numerous variants of itself, which can lead to pollution of the npm registry and potential security risks for developers using these packages.
Vulnerability Detail
The vulnerability in the melted_halibut_z3n package stems from its malicious code that modifies the package.json file to remove private flags, alters version numbers, and generates random package names. This behavior is indicative of a broader trend where malicious packages are used to inflate developer reputation scores for token rewards. The ramifications include the potential for developers to unknowingly install compromised packages, leading to security breaches and the proliferation of unwanted packages in the npm registry.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall melted_halibut_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 avoid using the melted_halibut_z3n package altogether and look for alternative packages that provide similar functionality without the associated risks. Additionally, regularly audit your npm packages using tools like npm audit to identify and address vulnerabilities.
Conclusion
The melted_halibut_z3n package poses a significant security risk due to its malicious code designed to manipulate npm package reputation scores. It is crucial for developers to remove this package from their projects and monitor their dependencies for vulnerabilities to maintain the integrity of their applications.
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FAQ
The melted_halibut_z3n package is an npm package that has been identified as malicious, designed to manipulate developer reputation scores through the automatic generation of derivative packages.
If your project uses the melted_halibut_z3n package, it may be at risk of installing malicious code that can compromise your application's security and pollute the npm registry.
You should uninstall the melted_halibut_z3n package immediately and check your package-lock.json for any lingering references to it. Consider using alternative packages.
You can use tools like npm audit to check for vulnerabilities in your npm packages. Additionally, services like Vulert can monitor your package-lock.json for real-time alerts on open-source vulnerabilities.
Yes, you can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without requiring any signup.
