There is a hack software(STEAM ID CHANGER). Someone with that hack go to some server, then they look for online admin.
When he see online admin he type in console "status" and copy admin steam:id. Then with that hack software he change their steam:id to admin steam:id and then he pick up all flags on that steam:id. Then he can ban all players on server.
So, for head admins. Put to your admins steam:id + "pw"
"STEAM:ID

xxxxxx231" "password" "ac" ; nick