Dot CGI pointing to localhost. What happened?

My ikiwiki broke. For some reason ikiwiki.cgi started pointing to https://localhost:80/ instead of the real URL. Can somebody help me find out why this has happened and perhaps fix it? Now login and recentchanges do not work because of it.

I believe the change happened after my hosting provider upgraded their server OS from Debian oldstable to stable. Rebuilding the .cgi or the wiki hasn't helped nor has helpdesk been helpful. Any hints as to debug this are appreciated.