criticalresolved
nginx-ui MCP unauthenticated command execution (CVE-2026-33032)
The nginx-ui MCP message endpoint performed no authentication on command-execution requests. An unauthenticated caller reaching the endpoint ran commands on the host. CVSS 9.8.
The nginx-ui MCP message endpoint performed no authentication on command-execution requests. Any caller that could reach the endpoint ran commands on the host with no credentials required. It scored CVSS 9.8.
Takeaway
An MCP server inherits every requirement a normal RPC endpoint carries, including authentication and authorization on anything that executes. Put an auth check in front of command execution and deny by default.
Sources
mcpnginx-uircemissing-authCVE-2026-33032