CVE-2025-66222: Thinkinai Deepchat

Critical severity, CVSS 9.6. EPSS: 0.6% chance of exploitation in the next 30 days.

DeepChat is a smart assistant uses artificial intelligence. In 0.5.0 and earlier, there is a Stored Cross-Site Scripting (XSS) vulnerability in the Mermaid diagram renderer allows an attacker to execute arbitrary JavaScript within the application context. By leveraging the exposed Electron IPC bridge, this XSS can be escalated to Remote Code Execution (RCE) by registering and starting a malicious MCP (Model Context Protocol) server.

Affected products

• Thinkinai Deepchat: up to and including 0.5.0

Published 2025-12-03. Last modified 2026-06-17.