What is crossdomain.xml and what should be in it?

The cPanel error log shows a recurring issue that the file crossdomain.xml does not exist. xenForo is installed in a directory off the site root called /forum, and accessed via a subdomain (forum.domain.com). It seems like I need a file called crossdomain.xml in the forum directory. What would that file consist of?


XenForo moderator
Staff member
crossdomain.xml is not a xenforo file.

Im guessing some bot is crawling your site for APIs/exploitable files and that is one it is looking for.