CSRF/XSRF protection different approach, is it safe?

[eluser]Jelmer[/eluser]
That wasn't the kind of access I was worried about. This is about CSRF attacks, attacks through such an application wouldn't typicly be CSRF attacks.

I was worried about an flash or java application requesting stuff from one of my sites while using my existing cookies/sessions. It shouldn't get access when coming from an external site, but when it changes its headers (like the HTTP_REFERER header) it would break the above security measure. And I was wondering wheter such an application would be authenticated with my existing cookies, or wheter it wouldn't be allowed to use those cookies...

No one any knowledge on the safety of the above?