---
id: CVE-2026-84318
title: Nginx UI is a web user interface for the Nginx web server
summary: >-
  Nginx UI is a web user interface for the Nginx web server. From 2.0.0-rc.6
  until 2.4.1, the MCP tool nginx_config_add writes nginx configuration files to
  disk and triggers an nginx reload without calling config.ValidateConfigFile.
  The id…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-693
published: '2026-10-12'
updated: '2026-10-12'
sourceUpdated: '2026-10-12T21:17:22.360'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-84318'
references:
  - url: >-
      https://github.com/0xJacky/nginx-ui/commit/23d1934099b05b2a01589b48129dc3d3159d91c2
    label: security-advisories@github.com
  - url: 'https://github.com/0xJacky/nginx-ui/releases/tag/v2.4.1'
    label: security-advisories@github.com
  - url: >-
      https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-9jww-cxg5-rj9m
    label: security-advisories@github.com
tags:
  - nvd
ingestedAt: '2026-10-12T22:05:40.368Z'
---

## Overview

Nginx UI is a web user interface for the Nginx web server. From 2.0.0-rc.6 until 2.4.1, the MCP tool nginx_config_add writes nginx configuration files to disk and triggers an nginx reload without calling config.ValidateConfigFile. The identical flow in the REST API (POST /api/configs) does call that function and correctly rejects dangerous directives. An authenticated attacker can exploit this gap to write config files containing any blocked directive (perl, js_import, load_module, user root, etc.), bypassing nginx-ui's entire security layer. On a server with the nginx Perl, njs, or Lua module loaded, this is post-authentication Remote Code Execution. This issue is fixed in version 2.4.1.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.