VULNERABILITY INTELLIGENCE

CVE-2026-33032

CVSS score9.8 CRITICAL
EPSS probability35.27%
CISA KEVNot currently listed
Published2026-03-30
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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.

Weakness classification

  • security-advisories@github.com: CWE-306

Primary references