MAL-2026-17846 Malicious code in @yudzxml/baileys (npm)

This package is a fork of the Baileys WhatsApp Web library. a static rule matched on keyword co-occurrence in lib/Utils/messages-media.js: require('child_process'), require('os'), require('http')/require('https'), and POST/GET/fetch( calls, with the only cited literal URL being https://mmg.whatsapp.net (WhatsApp's own media server, which is the expected destination for a Baileys media utility). The evidence quotes do not name any non-first-party attacker endpoint, do not show environment-variable scraping, and do not show reads of installer-secret paths (~/.ssh, ~/.aws, ~/.npmrc, browser stores). The primitive co-occurrence in messages-media.js is the shape you would expect from a legitimate WhatsApp media upload/download implementation (child_process for ffmpeg/thumbnail generation, http/https/fetch for WhatsApp media endpoints, os for tmpdir). Because this is a fork of a widely used upstream library, and forks are a common vehicle for covert modifications (e.g., undocumented actions using the caller's WhatsApp session), a reviewer should diff this fork against upstream Baileys to confirm messages-media.js only talks to mmg.whatsapp.net/WhatsApp infrastructure, and that no other file in the package performs credential harvest, undocumented auto-follow/subscribe, or exfiltration using the caller's session. Without corroborating evidence of installer harm, keyword co-occurrence alone is not sufficient to publish a block.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.