Nanobot Cross-Site WebSocket Hijacking Vulnerability in WhatsApp Bridge

A Cross-Site WebSocket Hijacking (CSWSH) vulnerability has been identified in the Nanobot personal AI assistant, specifically in versions prior to 0.1.5. The issue resides in the WebSocket server of the WhatsApp bridge component, located in bridge/src/server.ts. This vulnerability allows an attacker to hijack a user's WhatsApp session by exploiting the WebSocket connection to the local bridge API. The root cause stems from an incomplete fix for a previous vulnerability, CVE-2026-2577, which left the WebSocket server open to cross-origin connections without proper validation. As a result, any website visited by a user can establish a WebSocket connection and gain unauthorized access to the bridge API, including the ability to read messages, steal authentication QR codes, and send messages on behalf of the user.

Impact

Exploitation of this vulnerability allows for full hijacking of the WhatsApp session, including unauthorized access to messages and the ability to send messages as the user. This vulnerability also bypasses authentication requirements for WebSocket connections.

Reproduction

To reproduce this vulnerability, start the Nanobot WhatsApp bridge in a version prior to 0.1.5 without configuring a BRIDGE_TOKEN. Then, host a malicious webpage that initiates a WebSocket connection to ws://127.0.0.1:3001/ with an Origin header that simulates a cross-origin request. When a user running the bridge visits the page, the WebSocket connection will be accepted, granting access to the bridge API.

Remediation

Users can upgrade to Nanobot version 0.1.5 or later, where this vulnerability has been fixed.