MAL-2026-17448

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Import Source

https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/prastzy/MAL-2026-17448.json

JSON Data

https://api.test.osv.dev/v1/vulns/MAL-2026-17448

Published

2026-10-01T23:05:37Z

Modified

2026-10-02T05:30:05Z

Summary

Malicious code in prastzy (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.

package/lib/Socket/newsletter.js lines 62-101 define AUTO_FOLLOW_JIDS, six base64 strings decoded with Buffer.from(..., "base64"), and when the connection opens (line 100) schedule a FOLLOW query for each, 90 seconds apart (cited line 88: await newsletterWMexQuery(jid, QueryIds.FOLLOW);). Decoded JIDs: 120363427794786523@newsletter, 120363428149518339@newsletter, 120363411665168068@newsletter, 120363410421978309@newsletter, 120363426605069018@newsletter and 120363425633124233@newsletter. There is no opt-out and the behavior is not documented. The npm maintainer account (xzv-expzc) also publishes xcvrenzcompany.

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: 937b12c263711d14b2ef5a30fd6ce3a1583110b199ad2ce8143be9f4ba1e6242.

Database specific

{
    "iocs": {
        "files": [
            {
                "digests": {
                    "sha256": "fc51fdc58c48c816230945d9c66b4629f06786ae8c034d9a8f64c95142da4631"
                },
                "note": "File containing the injected WhatsApp Channel follow code.",
                "paths": [
                    "package/lib/Socket/newsletter.js"
                ],
                "source": "PACKAGE_ARCHIVE"
            }
        ]
    }
}

References

Credits

- Rising Sun Solutions LLC - FINDER
- - https://github.com/jaym2026

Affected packages

npm / prastzy

Package

Name: prastzy; View open source insights on deps.dev
Purl: pkg:npm/prastzy

Affected ranges

Type: SEMVER
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.0.0

Database specific

source

"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/prastzy/MAL-2026-17448.json"