npm · Malicious package advisory
Malwareyuuki-baileys
MAL-2026-19044
Malicious code in yuuki-baileys (npm)
Details
yuuki-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 Yuuki-baileys/lib/Socket/newsletter.js, lib/Socket/newsletter.js sends the WhatsApp w:mex FOLLOW query for the channel ID(s) 120363406005175144@newsletter, using the victim's authenticated session and without telling them. Same behaviour as the PhantomSub family (MAL-2026-17342).
Compromised versions (3)
- 1.0.1
- 2.0.0
- 2.1.0
Any computer that installed or ran a compromised version should be considered fully compromised. Rotate every secret on that machine from a clean environment.