Vulnerability · Published Mar 30, 2026 · Assigned by GitHub_M
CVE-2026-33032Nginx UI: Unauthenticated MCP Endpoint Allows Remote Nginx Takeover
Critical 9.8
In plain English
A critical-severity missing authentication in nginx-ui from 0xJacky. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 35.3% (higher than 98% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei, public proof-of-concept code.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/0xJacky/Nginx-UI | no fix listed | GHSA-h6c2-x2m2-mwhf |
| Go | github.com/0xJacky/Nginx-UI | no fix listed | GO-2026-4904 |
Affected products (as reported)
Weakness: CWE-306 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H