---
id: "CVE-2026-84360"
kind: "vulnerability"
aliases: ["CVE-2026-84360", "GHSA-vc32-4gwf-77xp", "GO-2026-6799"]
title: "Nginx UI: OTP secure-session step-up can be bypassed via MCP configuration tools in github.com/0xJacky/Nginx-UI"
severity: "high"
cvss: 8.1
epss: 0.00347
exploited: false
status: "open"
category: "package"
products: [{"name": "github.com/0xJacky/Nginx-UI", "fixed": ["1.9.10-0.20260703131214-23d1934099b0"], "affected": "< 1.9.10-0.20260703131214-23d1934099b0", "ecosystem": "go"}]
ecosystems: ["go"]
tags: ["go", "nginx", "nginx-ui", "package", "self-hosted"]
not_affected_if: ["no-mcp-exposure", "otp-disabled"]
published_at: "2026-10-12T21:17:22+00:00"
first_seen_at: "2026-10-23T19:13:08+00:00"
updated_at: "2026-10-23T19:52:45+00:00"
sources: [{"source": "govuln", "url": "https://pkg.go.dev/vuln/GO-2026-6799", "first_seen_at": "2026-10-23T19:13:08+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-84360", "first_seen_at": "2026-10-23T19:13:43+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-84360", "first_seen_at": "2026-10-23T19:35:23+00:00"}]
---

# Nginx UI: OTP secure-session step-up can be bypassed via MCP configuration tools in github.com/0xJacky/Nginx-UI

Nginx UI, a web interface for managing Nginx, lets an OTP-protected user skip the second-factor step-up check by calling its MCP endpoints. An attacker holding only a normal login token can create or modify Nginx configuration and trigger reloads.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- go:github.com/0xJacky/Nginx-UI affected < 1.9.10-0.20260703131214-23d1934099b0 fixed 1.9.10-0.20260703131214-23d1934099b0

## How to check

Confirm you run Nginx UI from the Go module github.com/0xJacky/Nginx-UI older than 1.9.10-0.20260703131214-23d1934099b0 (sources say fixed in 2.4.1 per the description).

## Fix

Upgrade Nginx UI to 2.4.1 or later (sources give fixed pseudo-version 1.9.10-0.20260703131214-23d1934099b0 for the Go module).
Rotate sessions and JWTs for users if exposure is suspected.

## Timeline

- 2026-10-23T19:13:08+00:00 govuln https://pkg.go.dev/vuln/GO-2026-6799
- 2026-10-23T19:13:43+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-84360
- 2026-10-23T19:35:23+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-84360

## From the sources

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.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_