CVE-2026-84360

Nginx UI: OTP secure-session step-up can be bypassed via MCP configuration tools

Published Oct 12, 2026 CVSS 3.1 · 8.1 High EPSS < 1% KEV · Not listed
Description
Nginx UI is a web user interface for the Nginx web server. Prior to 2.4.1, the HTTP configuration mutation routes require RequireSecureSession, but /mcp and /mcp_message require only ordinary authentication before exposing nginx_config_add and nginx_config_modify. An OTP-enabled user with a normal JWT but no valid X-Secure-Session-ID can therefore create or modify Nginx configuration and trigger reload behavior through MCP, bypassing the intended step-up control. This issue is fixed in version 2.4.1.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-vc32-4gwf-77xp Nginx UI: OTP secure-session step-up can be bypassed via MCP configuration tools
History
Type Values Removed Values Added
Metrics ssvc

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

Type Values Removed Values Added
First Time appeared 0xjacky
0xjacky nginx-ui
Vendors & Products 0xjacky
0xjacky nginx-ui
Type Values Removed Values Added
Description Nginx UI is a web user interface for the Nginx web server. Prior to 2.4.1, the HTTP configuration mutation routes require RequireSecureSession, but /mcp and /mcp_message require only ordinary authentication before exposing nginx_config_add and nginx_config_modify. An OTP-enabled user with a normal JWT but no valid X-Secure-Session-ID can therefore create or modify Nginx configuration and trigger reload behavior through MCP, bypassing the intended step-up control. This issue is fixed in version 2.4.1.
Title Nginx UI: OTP secure-session step-up can be bypassed via MCP configuration tools
Weaknesses CWE-288
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 13, 2026, 2:00 PM
Reserved
Sep 1, 2026, 4:27 PM
Status
Deferred
Published
Oct 12, 2026, 9:17 PM
Modified
Oct 13, 2026, 2:31 PM