wow, and yet another fail for cloudflare, thats just sad :) 

Paul not sure if it will help but maybe (if you can) edit and  add important! to your title, that might get there attention in case they dont know about this.   If not lets hope thats as bad as it gets.

Looking on it now it just appears that a user has mismanaged permissions perhaps. I have never used dokuwiki before but, https://www.dokuwiki.org/config:sneaky_index.