Re: What constitutes protection [was: About using CORS]

On Tue, May 4, 2010 at 3:57 PM, Jeffrey Veen <jeff@typekit.com> wrote:
> On Tue, May 4, 2010 at 2:19 PM, Levantovsky, Vladimir
> <Vladimir.Levantovsky@monotypeimaging.com> wrote:
>
>> It seems that same-origin restriction by default makes perfect sense for any resource,
>> and while I lament that it wasn't implemented for other resources, I do not see any
>> reason why it should not be in place for fonts and other resources going forward.
>
> Hasn't HTTP Referrer Checking been the solution to this thus far? As
> far back as I can remember, people have been using it to avoid
> hot-linking of images and other assets.

Referer checking can help here, but it does have issues that lead it
to getting filtered in the
network in some cases. I refer you to Adam Barth's paper, "Robust
Defenses for Cross-Site
Request Forgery" [1], that led to the proposal for the Origin header
(which is essentially
what CORS is using).

-- Dirk

[1] http://www.adambarth.com/papers/2008/barth-jackson-mitchell-b.pdf