Malicious Code Injection in bare_weasel_z3n: A Threat to npm Packages
Summary
MAL-2025-93354: Malicious code in bare_weasel_z3n (npm). Affected versions are not published. No fix is published. How to fix ↓
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Background
bare_weasel_z3n is an npm package that has been identified as part of a malicious campaign targeting the npm registry. This package is associated with the tea.xyz token reward initiative, which has been known to flood the npm ecosystem with derivative packages. These packages are designed to inflate developer reputation scores through automated publishing scripts, compromising the integrity of the npm registry.
Vulnerability Detail
The vulnerability in bare_weasel_z3n 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 leads to the continuous republishing of these 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 employs these tactics to manipulate the npm ecosystem.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
npm uninstall bare_weasel_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 remove the bare_weasel_z3n package from your project by running the command: npm uninstall bare_weasel_z3n. This will prevent any malicious code from executing until a proper fix is applied.
Conclusion
The bare_weasel_z3n package poses a significant threat due to its malicious code designed to manipulate the npm registry. It is essential to take immediate action by updating or uninstalling the package to safeguard your applications. Utilizing tools like Vulert can help monitor and alert for open-source vulnerabilities in real-time.
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FAQ
The malicious code modifies package.json files to remove private flags and generates random package names, leading to the pollution of the npm registry.
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The ramifications include the compromise of the npm registry's integrity, potential security risks for dependent packages, and manipulation of developer reputation scores.
Regularly updating dependencies, using tools like Vulert to monitor vulnerabilities, and auditing your package-lock.json can help prevent similar issues.
If an immediate update is not possible, consider uninstalling the package as a temporary measure to mitigate risks.
