Re: [TLS] Fingerprinting weaknesses (was: The risk of misconfiguration)

On Wed, May 7, 2014 at 3:07 PM, Nico Williams <nico@cryptonector.com> wrote:
> On Wed, May 7, 2014 at 2:04 PM, Alyssa Rowan <akr@akr.io> wrote:
>> On 07/05/2014 19:47, Viktor Dukhovni wrote:
>>
>>> This is not a compelling reason to remove protocol capabilities.
>>
>> I think that they are insecure _is_ a compelling reason: we seem
>> simply to disagree on that point.
>
> I disagree with your characterization.
>
>> More interestingly:
>>
>>> Cipher-suite signalling is just one of many ways that Mallory can
>>> determine which clients she can attack undetected.
>
> No.  Mallory can only see that anon ciphersuites where offered.
> Mallory cannot conclude from this that anon ciphersuites will be
> accepted (the peer might disconnect if an anon ciphersuite is
> negotiated) nor can Mallory conclude that channel binding (or renengo)
> won't be used in that session.  It's always a risk for Mallory to
> attempt an MITM attack.

So they do the MITM, see that SASL is being used, the connection
breaks, and then what?

Or they do the MITM, the peer disconnects because they didn't really
mean it anyway, and then what?

Sincerely,
Watson Ladd

>
> Nico
> --
>
> _______________________________________________
> TLS mailing list
> TLS@ietf.org
> https://www.ietf.org/mailman/listinfo/tls

-- 
"Those who would give up Essential Liberty to purchase a little
Temporary Safety deserve neither  Liberty nor Safety."
-- Benjamin Franklin