@billabilloyy/baileysnpm
Advisory published Updated
@billabilloyy/baileys is a confirmed malicious npm package (MAL-2026-18810) that executes malicious code on install (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in @billabilloyy/baileys (npm)
What this malware does
@billabilloyy/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 src/Socket/newsletter.js, src/WAUSync/Protocols/USyncNewsletterProtocol.js sends the WhatsApp w:mex FOLLOW query for the channel ID(s) 120363395678317603@newsletter, 120363400362472743@newsletter, 120363408893555851@newsletter, 120363426470081124@newsletter, 120363427718144294@newsletter and the channel invite code(s) 0029VbCX3x9Ae5VxVnDa172S, using the victim's authenticated session and without telling them. Same behaviour as the PhantomSub family (MAL-2026-17342).
Malicious versions
Detection & response playbook
Malicious packageFind it
Search your lockfiles and build artifacts for @billabilloyy/baileys (version 1.0.0).
If you installed it — respond
Remove @billabilloyy/baileys from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If @billabilloyy/baileys was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
References
Credits
- CyberXYZ · finder
Detect & block this
O3 blocks @billabilloyy/baileys-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.