nginx validates hostnames per the spec, and to your question specifically it rejects requests that would put a slash in $host: https://github.com/nginx/nginx/bl

nginx validates hostnames per the spec, and to your question specifically it rejects requests that would put a slash in $host: https://github.com/nginx/nginx/blob/b6e7eb0f5792d7a52d2675ee3906e502d63c48e3/src/http/ngx_http_request.c#L2221 https://github.com/nginx/nginx/blob/b6e7eb0f5792d7a52d2675ee...