Malicious code in @wanzlonely/bails4u (npm)
The npm package @wanzlonely/bails4u (versions 2.0.0, 3.0.0, 4.0.0, and 5.0.0) is part of a family of malicious forks of the Baileys WhatsApp Web library. These forks inject code that silently subscribes the victim's WhatsApp account to attacker-controlled channels using the victim's own authenticated session. The target channels are obfuscated or dynamically fetched, making detection difficult. The malicious code does not exfiltrate credentials, establish persistence, or execute arbitrary remote code.
AI Analysis
Technical Summary
The @wanzlonely/bails4u package contains injected code that hooks into the WhatsApp socket connection routine to issue an authenticated 'w:mex' FOLLOW query to attacker-chosen WhatsApp Channel/Newsletter JIDs shortly after connection. This causes the victim's WhatsApp account to subscribe to channels without their consent. The target JIDs are hidden via various obfuscation methods or fetched dynamically from attacker-controlled remote sources. This behavior leverages the installer's authenticated WhatsApp session to propagate subscriptions but does not perform credential theft, persistence, or remote code execution.
Potential Impact
Victims unknowingly subscribe their WhatsApp accounts to attacker-controlled channels, potentially exposing them to unwanted content or spam. The attack abuses the victim's authenticated session to increase reach for malicious channels. There is no direct credential theft, persistence, or arbitrary code execution reported.
Mitigation Recommendations
No official patch or remediation is currently documented. Users should avoid installing or using the affected versions of @wanzlonely/bails4u (2.0.0, 3.0.0, 4.0.0, 5.0.0). Review dependencies carefully and consider removing or replacing this package. Monitor for updates from the package maintainer or npm advisories for any future fixes.
Malicious code in @wanzlonely/bails4u (npm)
Description
The npm package @wanzlonely/bails4u (versions 2.0.0, 3.0.0, 4.0.0, and 5.0.0) is part of a family of malicious forks of the Baileys WhatsApp Web library. These forks inject code that silently subscribes the victim's WhatsApp account to attacker-controlled channels using the victim's own authenticated session. The target channels are obfuscated or dynamically fetched, making detection difficult. The malicious code does not exfiltrate credentials, establish persistence, or execute arbitrary remote code.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The @wanzlonely/bails4u package contains injected code that hooks into the WhatsApp socket connection routine to issue an authenticated 'w:mex' FOLLOW query to attacker-chosen WhatsApp Channel/Newsletter JIDs shortly after connection. This causes the victim's WhatsApp account to subscribe to channels without their consent. The target JIDs are hidden via various obfuscation methods or fetched dynamically from attacker-controlled remote sources. This behavior leverages the installer's authenticated WhatsApp session to propagate subscriptions but does not perform credential theft, persistence, or remote code execution.
Potential Impact
Victims unknowingly subscribe their WhatsApp accounts to attacker-controlled channels, potentially exposing them to unwanted content or spam. The attack abuses the victim's authenticated session to increase reach for malicious channels. There is no direct credential theft, persistence, or arbitrary code execution reported.
Mitigation Recommendations
No official patch or remediation is currently documented. Users should avoid installing or using the affected versions of @wanzlonely/bails4u (2.0.0, 3.0.0, 4.0.0, 5.0.0). Review dependencies carefully and consider removing or replacing this package. Monitor for updates from the package maintainer or npm advisories for any future fixes.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- MAL-2026-17381
- Osv Schema Version
- 1.7.4
- Ecosystems
- ["npm"]
Threat ID: 6abd30852a4e24523d340147
Added to database: 09/30/2026, 15:53:41 UTC
Last enriched: 09/30/2026, 16:03:35 UTC
Last updated: 09/30/2026, 22:39:15 UTC
Views: 2
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