The npm package xzvbails (version 0.0.1) 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. This is done by issuing an authenticated FOLLOW query using the victim's own WhatsApp session. The targeted channel JIDs are obfuscated or fetched remotely, allowing dynamic control by the attacker. The malicious code does not steal credentials, maintain persistence, or execute arbitrary code beyond this subscription action.