Description
Nginx UI is a web user interface for the Nginx web server. In versions 2.3.5 and prior, the nginx-ui MCP (Model Context Protocol) integration exposes two HTTP endpoints: /mcp and /mcp_message. While /mcp requires both IP whitelisting and authentication (AuthRequired() middleware), the /mcp_message endpoint only applies IP whitelisting - and the default IP whitelist is empty, which the middleware treats as "allow all". This means any network attacker can invoke all MCP tools without authentication, including restarting nginx, creating/modifying/deleting nginx configuration files, and triggering automatic config reloads - achieving complete nginx service takeover. At time of publication, there are no publicly available patches.
Problem types
CWE-306: Missing Authentication for Critical Function
Product status
References
github.com/...inx-ui/security/advisories/GHSA-h6c2-x2m2-mwhf
websec.net/...nginx-ui-mcp-takeover-69e1200f9fceb1f3fbe9c47f
github.com/...inx-ui/security/advisories/GHSA-h6c2-x2m2-mwhf