[whatwg] Sandboxed IFrames and downloads.

[James Ross]

A quick test across browsers would suggest others think it is a reasonable protection to include: both Internet Explorer 10 and Firefox 18 block (ignore) the download attempt in the sandboxed <iframe>.
  
 I couldn't find any documentation on either browser doing this, though, or if they have a sandbox flag to allow it.

-- 
James Ross silver at warwickcompsoc.co.uk
 > From: mkwst at google.com
> Date: Fri, 15 Feb 2013 09:08:35 +0100
> To: whatwg at whatwg.org
> Subject: Re: [whatwg] Sandboxed IFrames and downloads.
> 
> Ping. Is this a terrible idea? :)
> 
> --
> Mike West <mkwst at google.com>, Developer Advocate
> Google Germany GmbH, Dienerstrasse 12, 80331 München, Germany
> Google+: https://mkw.st/+, Twitter: @mikewest, Cell: +49 162 10 255 91
> 
> 
> On Sat, Feb 2, 2013 at 7:11 PM, Mike West <mkwst at google.com> wrote:
> 
> > It's currently possible to force a download by serving a file with a
> > "Content-Disposition: attachment; filename=..." header. Notably, this
> > mechanism can be used to download a file with minimal user interaction by
> > including the resource to be downloaded in an IFrame. This holds even for
> > sandboxed IFrames, as demonstrated by
> > http://lcamtuf.coredump.cx/sandboxed.html (clicking that link will
> > download a file, fair warning).
> >
> > It seems consistent with the general thought behind the `sandbox`
> > attribute that it should control downloads as well as the bits it already
> > locks down. I'd propose adjusting the spec to include a sandboxed downloads
> > flag, which, when present, would block all downloads from inside the frame
> > (or, perhaps only require user confirmation?). This restriction could be
> > lifted via an 'allow-downloads' keyword, if present in the sandbox
> > attribute's token list.
> >
> > WDYT?
> >
> > --
> > Mike West <mkwst at google.com>, Developer Advocate
> > Google Germany GmbH, Dienerstrasse 12, 80331 München, Germany
> > Google+: https://mkw.st/+, Twitter: @mikewest, Cell: +49 162 10 255 91
> >