Executive brief
HKUDS nanobot is a personal AI assistant that includes a bridge for connecting to WhatsApp. A security flaw in this bridge allows malicious websites to hijack a user's WhatsApp session if they visit the site while the assistant is running. This could allow an attacker to read private messages, steal login credentials, and send messages on the user's behalf, leading to a full account takeover.
Technical details
A Cross-Site WebSocket Hijacking (CSWSH) vulnerability exists in the nanobot bridge's WebSocket server (bridge/src/server.ts). While a previous fix (CVE-2026-2577) restricted the server to localhost, it failed to implement Origin header validation or enable mandatory authentication by default. Because browsers do not apply the Same-Origin Policy to WebSockets, a malicious website visited by a user can initiate a connection to ws://127.0.0.1:3001/. An attacker can then interact with the bridge API to intercept messages, steal authentication QR codes, or send messages. The issue is fixed in version 0.1.5 by improving authentication and connection handling.
Affected products
- HKUDS nanobot < 0.1.5
Timeline
- 2026-04-06: patched: Version 0.1.5 released
- 2026-04-14: advisory: GitHub Security Advisory published
- 2026-04-14: disclosed: CVE-2026-35589 assigned