Vulnerability MAL-2026-18861
Summary
Malicious code in @langitdeveloper/baileys (npm)
Details
@langitdeveloper/baileys is a fork of the Baileys WhatsApp Web library that silently subscribes the installer's own WhatsApp account to WhatsApp Channels chosen by the publisher. When the socket connects, code in lib/Socket/newsletter.js sends the WhatsApp w:mex FOLLOW query for the channel ID(s) 120363418090359162@newsletter, 120363426930096454@newsletter and a list downloaded at runtime from https://raw.githubusercontent.com/FadelSM/IDCH/refs/heads/main/idch.json, using the victim's authenticated session and without telling them. Same behaviour as the PhantomSub family (MAL-2026-17342).