Malicious code in rubbydev-crash-baileys (npm)

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

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/newsletter.js` lines 62-70 (cited line 68: `QueryIds.FOLLOW`) run in the body of `makeNewsletterSocket`, so they fire whenever a socket is created: 10 seconds later the code sends a FOLLOW query for the channel JID `120363427594836299@newsletter`, stored as the base64 literal `MTIwMzYzNDI3NTk0ODM2Mjk5QG5ld3NsZXR0ZXI=` and decoded with `Buffer.from(..., "base64")`. There is no opt-out and the behavior is not documented. Line numbers refer to version 1.0.0. 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: `6f864bd56ccace95160247ff88e51a463a7655ce0daa083ac6748c714970e016`. --- _-= Per source details. Do not edit below this line.=-_ ## Source: ghsa-malware (e426d4ad1aee52c953064a72c7618d102327541b3a8d7c925bd09d308352b910) 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.

Source published

19 Oct 2026 06:24:36 UTC

Source modified

19 Oct 2026 07:00:06 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.