RE: Strong Authentication

["Jason Mafera" <jmafera () IMPRIVATA com>]

This is mutual authentication, not multi factor.  In this scenario the
you auth to the bank with the certificate, and the bank proves it is who
you expect with it's certificate.  Very similar to Sitekey technology
(RSA, formerly Cyota and Passmark) where the bank will post back a
picture that you had selected during enrollment to prove you are at the
correct website.

For this to be a multi factor authentication, the private key of the
certificate would need to be protected (ideally on a smartcard) with a
user pin that is needed to decrypt the key before passing it for
authentication.

-Jason

Jason Mafera, CISSP

-----Original Message-----
From: listbounce () securityfocus com [mailto:listbounce () securityfocus com]
On Behalf Of Mark Dy-Ragos
Sent: Tuesday, May 13, 2008 1:17 PM
To: security-basics () securityfocus com
Subject: Strong Authentication

Dear All,

On most of the references I've read, strong authentication is defined
as having 2 or more of the following:

Something you know
Something you have
Something you are (or do)

However, after reading some vendor websites, I'm a little more
confused as to the exact interpretation of this.

For example, Comodo touts their digital signature solution as a form
of 2 factor authentication [1]

=================
Comodo Two Factor Authentication Solution

1) Client Digital Certificates to authenticate the user to the bank
(Part 1 of the two factor authentication)
2) Content Verification Certificates (CVC) to authenticate the FI
website to the user (Part 2 of the two factor authentication)
=================

However, to me, this doesn't seem to fit 2 out of the 3 criteria
listed above.  To be honest, I'm not sure which category a digital
signature would fall under.

Can anyone share their feedback on this?  A different vendor that we
plan on using is telling us that through the use of digital
signatures, we will be implementing strong authentication, but I'm not
too clear on how this accomplishes it.

Thanks,
Mark

[1] http://www.comodo.com/banking/twofactor.html

"Level 3- Level 3 provides multi-factor remote network authentication.
At this level, identity proofing procedures require verification of
identifying materials and information. Level 3 authentication is based
on proof of possession of a key or a one-time password through a
cryptographic protocol. Level 3 authentication requires cryptographic
strength mechanisms that protect the primary authentication token
(secret key, private key or one-time password) against compromise by
the protocol threats including: eavesdropper, replay, on-line
guessing, verifier impersonation and man-in-the-middle attacks. A
minimum of two authentication factors is required. Three kinds of
tokens may be used: "soft" cryptographic tokens, "hard" cryptographic
tokens and "one-time password" device tokens."
[2] http://csrc.nist.gov/publications/nistpubs/800-63/SP800-63V1_0_2.pdf