The server committed a protocol violation. Section=ResponseHeader Detail=CR must be followed by LF [closed]

Question

I've tested my website with mxtoolbox.com and got this message:

Result: The server committed a protocol violation. Section=ResponseHeader Detail=CR must be followed by LF

I've googled around but I've only found Microsoft related answers that have nothing to do with my webserver. My server is Linux based Centos 6.6 with Nginx 1.8.0 webserver.

Here is the test: http://mxtoolbox.com/domain/poxi.net/?source=findmonitors

What have I tried?

• I've tried upgrading Nginx from 1.7.12 to 1.8.0 and it didn't help.
• I've tried changing Nginx config by commenting almost everything, but it didn't help.

Does anyone have any idea what this error means and how to fix it?

Thanks!

Answer 1

I've found the problem. I was hardening webserver and followed one tutorial which suggested changing nginx source code.

It suggested to change:

static char ngx_http_server_string[] = "Server: nginx" CRLF;
static char ngx_http_server_full_string[] = "Server: " NGINX_VER CRLF;

to somethig else.

I changed it to:

static char ngx_http_server_string[] = "WebServer" CRLF;
static char ngx_http_server_full_string[] = "WebServer" CRLF;

Now I've changed it back to original and recompiled. Error is gone now.