[whatwg] crossorigin property on iframe

Adam Barth w3c at adambarth.com
Thu Apr 12 12:42:15 PDT 2012

Would this be transitive?  Suppose A allows B with CORS and B allows
C.  What happens when C includes a frame to B and B includes a frame
to A?  Can C access A?  Based on your description, it sounds like
"yes", but there's widespread evidence that transitive trust is


On Thu, Apr 12, 2012 at 12:30 PM, Ojan Vafai <ojan at chromium.org> wrote:
> We should add a crossorigin property on iframe that causes the request to
> use CORS. If it's an allowed cross-domain request, then the page should
> have access to the DOM of the frame.
> Also, seamless should work (assuming the CORS request succeeded of
> course). One tricky thing here is that seamless needs to stop working if
> the frame is navigated to a different origin to which it does not have CORS
> access.
> Ojan

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