9.8

CVE-2026-33032: Nginx UI: Unauthenticated MCP Endpoint Allows Remote Nginx Takeover

Modified
AliasesGHSA-h6c2-x2m2-mwhfGO-2026-4904
Published 30-03-2026Last modified 16-04-2026

Vulnerability summary

CVE-2026-33032 is a critical (CVSS 9.8) vulnerability in 0xjacky nginx-ui. EPSS estimates a 35.27% chance of exploitation in the next 30 days, higher than 98.4% of scored vulnerabilities. 1 public exploit is recorded.

Priority
Prioritisepublic exploit

Public exploit (GitHub, Date unknown)

Source freshness unavailable

How is this decided?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
35.27%
0%100%
High · +32.75 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits1github

Advisory lineage

Upstream 0 · Downstream 2 · Related 2
OPENSUSE-SU-2026:21483-1SUSE-SU-2026:1205-1

Timeline

  1. 30-03-2026
    PublishedVulnerability first disclosed.
  2. 16-04-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

35.27%

Chance of exploitation in the next 30 days

Percentile

98%

Versus all other CVEs

30-day change

Increase +32.75 pp

From 2.52% on 05-10-2026

05-10-202604-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

1 found
  • githubUnverified

    Nginx Ui

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

0xjacky1 product
Github.com/0xJacky1 product
  • Nginx-UI≤ 1.99 | All versions (No fix recorded)
Nginxui1 product

3 vendors · 3 products

References

6 links