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.
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-9jww-cxg5-rj9m Nginx UI: MCP `nginx_config_add` Bypasses Directive Validation — Authenticated RCE
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 13 Oct 2026 15:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Mon, 12 Oct 2026 22:00:00 +0000

Type Values Removed Values Added
First Time appeared 0xjacky
0xjacky nginx-ui
Vendors & Products 0xjacky
0xjacky nginx-ui

Mon, 12 Oct 2026 20:45:00 +0000

Type Values Removed Values Added
Description 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.
Title Nginx UI: MCP `nginx_config_add` Bypasses Directive Validation — Authenticated RCE
Weaknesses CWE-693
References
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-10-13T14:59:04.180Z

Reserved: 2026-09-01T16:17:43.079Z

Link: CVE-2026-84318

cve-icon Vulnrichment

Updated: 2026-10-13T14:58:17.853Z

cve-icon NVD

Status : Deferred

Published: 2026-10-12T21:17:22.360

Modified: 2026-10-13T15:17:50.383

Link: CVE-2026-84318

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-12T21:45:17Z

Weaknesses