The npm package 'whs4_deu' versions 1.0.0 and 1.0.1 contains malicious code that executes during installation. Specifically, a postinstall script runs a JavaScript file that sends the installer's absolute file path, Node.js version, and platform details to a hardcoded Discord webhook. This behavior is undocumented and the webhook URL is obfuscated to evade detection. The package provides no legitimate functionality and is flagged as malicious due to its communication with a domain linked to malicious activity.