On Wed, Nov 12, 2014 at 7:27 PM, Jason Greene <jason.greene@redhat.com> wrote: > > > On Nov 12, 2014, at 4:40 PM, Eric Rescorla <ekr@rtfm.com> wrote: > > > >> On Tue, Nov 11, 2014 at 8:58 PM, Greg Wilkins <gregw@intalio.com> > wrote: > >> > >> I think it is a downgrade attack vector, but what I think this WG is > trying to say is that it is an acceptable one. If either peer wants to > avoid it, they simple need to not offer the bad ciphers. > >> > > Can you please explain how this downgrade attack works? > > In order to deal with servers which, perhaps mistakenly, accept non-h2 > compliant ciphers, a client has to choose between failing the connection > entirely (when H1 would have worked fine), or opening a new connection. If > that new connection offers a weaker selection of ciphers (perhaps some kind > of fallback to an old code path) it becomes a potential target. Can you explain how the attacker exploits that? -Ekr > -- > Jason T. Greene > WildFly Lead / JBoss EAP Platform Architect > JBoss, a division of Red Hat > >
Received on Thursday, 13 November 2014 16:35:57 UTC