The kasabaileys npm package is a malicious fork of the Baileys WhatsApp Web library that injects code to silently subscribe the victim's WhatsApp account to attacker-controlled channels without user consent. It uses the victim's authenticated WhatsApp session to issue a covert FOLLOW query to subscribe to these channels. The target channels are obfuscated or dynamically fetched to evade detection. This behavior does not steal credentials, maintain persistence, or execute arbitrary code. Affected versions include 0.3.15, 1.0.0, 1.0.1, and 1.0.2.