Comment to above post:
Over at vbulleting.com Steve Machol has posted some views regarding this issue
http://www.vbulletin.com/forum/showthread.php?t=268862
In the case of third party he links right back to us at vbulleting.org for the following article that explains the new protection scheme against Cross Site Request Forgery (CSRF) that exploits the stateless nature of HTTP.
https://vborg.vbsupport.ru/showthread.php?t=177013
I think we should take a closer look at the last link and update this excellent chatBox accordingly.