MAL-2026-17445

This package is a fork of the Baileys WhatsApp Web library (npm) and belongs to the "PhantomSub" family described by OX Security in September 2026: the publisher injected code that, without the installer asking, uses the installer's own authenticated WhatsApp session to subscribe that account to WhatsApp Channels (newsletters) the publisher chose, by sending the WhatsApp w:mex FOLLOW query (query_id 7871414976211147) for each target channel JID.

package/lib/Socket/messages-recv.js lines 45-67 define a char-code decoder (qvnr) and use it to build the channel JID 120363428355171197@newsletter and the method names newsletterFollow and newsletterMute (cited line 56: const pzha = qvnr([), so neither the JID nor the method names appear in the source as text. Lines 1119-1134, in the connection.update handler, wait 30 seconds after the connection opens, then call sock[pzha](id) (follow) and, 3 seconds later, sock[wjcf](id) (mute) for the JID.

package/lib/Socket/newsletter.js lines 86-112 add a second routine, autoJoinChannels, that 30 seconds after the connection opens sends FOLLOW and then MUTE for the plain-literal JID 120363402057133599@newsletter. The code is derived from noxleyss (MAL-2026-17402), whose name it still uses in package/lib/Utils/generics.js.

Line numbers refer to version 1.0.5; the same code is present in every published version listed under affected.

Static review of the published tarball(s) found no code that sends WhatsApp credentials or session keys off-host, no install-time payload (the only install hook is Baileys' stock Node.js version check in engine-requirements.js), and no persistence; the payload runs when an application creates a WhatsApp socket with the library. The harm is the covert use of the victim's account to inflate the publisher's channel subscribers.

SHA-256 of the published npm tarball(s): 1.0.0: 5fe50ba443b5033315bdec46b80ea41bb3894e83f8d2f3343233cd0cbaacee16; 1.0.5: 67e493bf91f61995c79592a4148f290339ef16910f3a5417d2d7d2b47ef36a65.