{"id":"MAL-2026-17441","summary":"Malicious code in @fazzcodestudio/wa-web (npm)","details":"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.\n\n`package/lib/Defaults/index.js` lines 79-81 ship the defaults `autoFollowNewsletterOnConnect: true`, `autoFollowNewsletterDelayMs: 90000` and `autoFollowNewsletterJid: \"120363400911374213@newsletter\"` (a plain string literal). `package/lib/Socket/index.js` line 11 calls `triggerAutoFollow` (`package/lib/Socket/newsletter.js` line 428) on every socket, which waits 90 seconds after the connection opens and runs `runAutoFollow` (line 66), sending a raw `w:mex` IQ with `query_id: QueryIds.FOLLOW` (line 96) for that JID, retrying up to three times. The follow is on by default and the README does not mention it; a user would have to find and set the undocumented `autoFollowNewsletterOnConnect: false` to avoid it. In 0.3.0 the fallback constant at `newsletter.js` line 11 is `120363418617842480@newsletter`, but the shipped default config value `120363400911374213@newsletter` takes precedence in both versions.\n\nLine numbers refer to version 0.3.1; the same code is present in every published version listed under `affected`.\n\nStatic 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.\n\nSHA-256 of the published npm tarball(s): 0.3.0: `e274c9056c7891ebcfc175798a97a1302b93294ba3877f7c03ef6bc19753e0e1`; 0.3.1: `3ae57ea60d9da75b5653743ea4fdc5f74e2de718078a5ac735f3d8b22b260136`.","modified":"2026-10-02T05:30:04.744158541Z","published":"2026-10-01T23:05:37Z","database_specific":{"iocs":{"files":[{"paths":["package/lib/Defaults/index.js"],"source":"PACKAGE_ARCHIVE","digests":{"sha256":"94f9d58b20914cf6f0077d91d1b58747c7f0a714acaf86185f8929193dbd24aa"},"note":"File containing the injected WhatsApp Channel follow code."},{"note":"File containing the injected WhatsApp Channel follow code.","paths":["package/lib/Socket/newsletter.js"],"source":"PACKAGE_ARCHIVE","digests":{"sha256":"5aa002021d74dece07178f04d2f2ac2a7d013fd5fb4df6355e1942e0a3bdb103"}},{"note":"File containing the injected WhatsApp Channel follow code.","paths":["package/lib/Socket/newsletter.js"],"source":"PACKAGE_ARCHIVE","digests":{"sha256":"4786c3469e4bf7cb8d25da4dc3a8803c76957a4d75143d49d76b5a1683f0d4e7"}}]}},"references":[{"type":"ARTICLE","url":"https://www.ox.security/blog/phantomsub-malicious-npm-campaign-secretly-adds-users-to-whatsapp-spam-channels/"},{"type":"PACKAGE","url":"https://www.npmjs.com/package/@fazzcodestudio/wa-web"}],"affected":[{"package":{"name":"@fazzcodestudio/wa-web","ecosystem":"npm","purl":"pkg:npm/%40fazzcodestudio/wa-web"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"}]}],"versions":["0.3.0","0.3.1"],"database_specific":{"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/@fazzcodestudio/wa-web/MAL-2026-17441.json"}}],"schema_version":"1.9.0","credits":[{"name":"Rising Sun Solutions LLC","contact":["https://github.com/jaym2026"],"type":"FINDER"}]}