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

[madaroda]

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?

 

[Slavik]

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.

 

[Mike]

Crossdomain.xml is related to Flash: http://www.adobe.com/devnet/articles/crossdomain_policy_file_spec.html

 

[digitalpoint]

If only Internet Explorer had better support for XHR file uploads, you wouldn't need Flash any longer (I think that's all it's used for in XenForo)...

http://blueimp.github.com/jQuery-File-Upload/
https://github.com/blueimp/jQuery-File-Upload/wiki/Frequently-Asked-Questions

 

[madaroda]

Where is Flash used in xenForo? And what should the contents of crossdomain.xml be to support it?

 

[Russ]

Where is Flash used in xenForo? And what should the contents of crossdomain.xml be to support it?

I think it's flash when you go to upload files with a post.