CVE-2026-33032 Nginx UI: Unauthenticated MCP Endpoint Allows Remote Nginx Takeover
Unauthenticated access to the MCP endpoint allows remote attackers to modify Nginx configurations and restart the service, leading to full service takeover.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-33032?
CVE-2026-33032 is a critical missing authorization vulnerability in 0xJacky nginx-ui, published on 30 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-306
Which versions are affected by CVE-2026-33032?
3 open source packages ship an affected version, including github.com/0xJacky/Nginx-UI. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/0xJacky/Nginx-UI Go | All versions | None |
github.com/0xJacky/Nginx-UI Go | All versions to 1.99 | None |
github.com/0xJacky/Nginx-UI Go | All versions to 1.99 | None |
Products include Nginxui Nginx Ui.
How do I fix CVE-2026-33032?
No fix published yet.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-33032 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33032 exists.
Public exploit code: 1 Nuclei template and 4 proofs of concept on GitHub.
Other vulnerabilities in 0xJacky nginx-ui
- CVE-2026-27944 Nginx UI: Unauthenticated Backup Download with Encryption Key Disclosure
- CVE-2024-23827 Nginx-UI arbitrary file write through the Import Certificate feature
- CVE-2026-107806 Nginx UI: Authenticated Remote Code Execution via Backup Restore App Config Overwrite
- CVE-2026-33026 nginx-ui Backup Restore Allows Tampering with Encrypted Backups
- CVE-2026-42238 Unauthenticated Remote Code Execution via Backup Restore in nginx-ui
Sources
Also known as GHSA-h6c2-x2m2-mwhf, GO-2026-4904.