Re: CSR and Mozilla - Clarifying HTTP Header Filtering

On 2/20/08, Henri Sivonen <hsivonen@iki.fi> wrote:
> On Feb 20, 2008, at 20:42, Mark Baker wrote:
>
> > It's not a new attack vector, because I can already use curl to send a
> > GET message which causes the harm you're worried about.  AFAICT, all
> > that changes in a cross-site scenario is that the attacker uses the
> > client as an anonymizer, something that can already be done with open
> > proxies (of various flavours).
>
>
> What changes is that the browser in on the other side of the firewall
> unlike curl or an open proxy.

Hmm, good point.  Come to think of it, we've discussed this before.
But in that case, the attack is upon firewalls, not broken servers.
So it seems to me that we'd only need to prevent hop-by-hop headers
from being set (by treating the Connection header as immutable), as
that's the only way in HTTP 1.1 to address an intermediary.  What do
you think?

Mark.
-- 
Mark Baker.  Ottawa, Ontario, CANADA.         http://www.markbaker.ca
Coactus; Web-inspired integration strategies  http://www.coactus.com

Received on Wednesday, 20 February 2008 19:49:59 UTC