xzvbailss

GHSA-pr4w-wjwf-c2g3

Malicious code in xzvbailss (npm)

Details

**Severity:** Critical

**Affected versions:** `= 1.0.0`

xzvbailss 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 lib/Socket/newsletter.js sends the WhatsApp w:mex FOLLOW query for the channel ID(s) 120363400505489366@newsletter, 120363430764800148@newsletter (stored base64-encoded), using the victim's authenticated session and without telling them. Same behaviour as the PhantomSub family (MAL-2026-17342).

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Credit: [OpenSSF](https://github.com/ossf/malicious-packages) ([source](https://github.com/ossf/malicious-packages/blob/23ba843b4a773277fa7a4a51240e83cd70ea2a45/osv/malicious/npm/xzvbailss/MAL-2026-18702.json))

**References:**
- https://github.com/ossf/malicious-packages/blob/23ba843b4a773277fa7a4a51240e83cd70ea2a45/osv/malicious/npm/xzvbailss/MAL-2026-18702.json
- https://www.npmjs.com/package/xzvbailss
- https://www.ox.security/blog/phantomsub-malicious-npm-campaign-secretly-adds-users-to-whatsapp-spam-channels
- https://github.com/advisories/GHSA-pr4w-wjwf-c2g3

Compromised versions (1)

= 1.0.0

Any computer that installed or ran a compromised version should be considered fully compromised. Rotate every secret on that machine from a clean environment.