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RE: MS crypto API based ssl proxy??
From: "Gaziel, Avishay" <avishaygaziel () kpmg com>
Date: Wed, 7 Jan 2004 18:12:46 +0100

I would try getting (or generating using openSSL) a set of client
certificates with popular user/password combinations, or, if you have a list
of users (a corporate phone list would do)I would create a few certificates
for these users as well. openssl/stunnel/sslproxy have all been used for
It's not much but might work.....

-----Original Message-----
From: Shashank Rai [mailto:shashrai () emirates net ae]
Sent: 07 January 2004 04:37
To: Volker Tanger
Cc: pen-test () securityfocus com
Subject: Re: MS crypto API based ssl proxy??

It maybe uses the Micro$oft NTLM authentication scheme - or similar.
What does a packet sniffer tell you, what happens?


Volker Tanger

It is nothing to do with NTLM auth (or for that matter basic auth). When
i browse the site using IE, i am prompted to provide the user
certificate. Running stunnel/sslproxy in debug mode clearly show the
server requesting the client certificate.
Packet sniffer is good only to the extent of showing me TLS v1 hand
shake (and ofcourse the remaining conversation is encrypted). 
I belive the site is M$ specific, 'coz, sslproxy/stunnel manage to
complete the SSL handshake, and open a connection to the server. But the
moment i send a "GET / HTTP/1.0" request, the connection is closed from
the server end, stating that the client certificate i provided is not
valid (the certificate had been exported from IE, along with the private
key). Hence the conclusion that the calls made to check the validity of
the certificate are someway M$ specific!!! (as stated in my original

Thanks anyway :)


Here is the Packet that was fragmented and has been assembled again.
                                       (with apologies to JRR Tolkien :)


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