registry / spencer-baileys / 1.0.4

spencer-baileys@1.0.4

WebSocket-based JavaScript library for interacting with the WhatsApp Web API

AI Security Review

scanned 12d ago · by lpm-firewall-ai

Creating a WhatsApp socket through the published entrypoint silently follows a publisher-chosen newsletter about 90 seconds later, using the caller's authenticated session. A leftover backup shows the same follow loop driven by a remote JSON list.

Static reason

One or more suspicious static signals were detected.; source matched previously finalized malicious package; routed for review

Trigger

Any caller that constructs the default makeWASocket / makeMessagesSocket stack.

Impact

The linked WhatsApp account subscribes to a third-party newsletter without a user follow action. The unused backup would let a remote file change which channels are followed.

Mechanism

makeNewsletterSocket starts a timer, base64-decodes a channel id, resolves it if needed, and sends a hidden follow query to s.whatsapp.net while swallowing errors.

Attack narrative

Importing this Baileys fork and opening a socket runs makeNewsletterSocket on the default stack. After 90 seconds it decodes a hardcoded newsletter id, resolves an invite code when needed, and sends a follow query on the user's WhatsApp session. Failures are ignored, so the subscription is not surfaced as a library error. A sibling backup of the same function instead downloads the id list from files.gifted.co.ke; that file is not loaded, but it shows the same unsolicited follow design.

AI rationale

The published socket path silently subscribes the connected WhatsApp account to a publisher-selected newsletter, which is concrete unconsented account abuse. The obfuscated timer, swallowed errors, and remote-list backup show intentional stealth rather than a documented API.

Evidence

lib/Socket/newsletter.jslib/Socket/messages-send.jslib/Socket/messages-recv.jslib/Socket/business.js

This package is part of a large family (100+ identified as of September 2026) of near-identical forks of the Baileys WhatsApp Web library that inject a covert channel-subscription action into the WhatsApp socket layer. On connect, the injected code issues an authenticated `w:mex` FOLLOW query (query_id 7871414976211147) against one or more attacker-chosen WhatsApp Channel/Newsletter JIDs, using the installer's own authenticated WhatsApp session -- silently subscribing the victim's account to channels it never asked to join. The target JID(s) are hidden from casual source review via one of several obfuscation techniques observed across the family: a plain string literal, base64 encoding, base64+XOR, or a char-code array reconstructed at runtime. Some variants instead fetch a mutable, attacker-controlled remote JSON/JS list of target JIDs from GitHub or another host at runtime, letting the target list change after installation without a new npm publish. Every sample in the family shares the same underlying mechanism (a wrapped/patched socket-connect routine that fires the FOLLOW query some seconds after connect), even though the package name, JID value(s), and obfuscation/delivery method differ per fork. The malicious action abuses the installer's own authenticated WhatsApp session to gain reach and subscribers for attacker-controlled channels; it does not exfiltrate credentials, establish persistence, or execute arbitrary remote code. Affected package: spencer-baileys (npm), version(s): 1.0.4.

spencer-baileys@1.0.4

AI Security Review

OSV advisory

Decision evidence

Source & flagged code

Source & flagged code

Findings

Affected versions and remediation

Source & flagged code