Re: OpenID. The future of authentication on the web?

[Paul Schmehl <pauls () utdallas edu>]

--On March 23, 2008 2:52:53 PM +0000 "Petko D. Petkov" 
<pdp.gnucitizen () googlemail com> wrote:
> First of all, OpenID is a very simple but rather useful technology.
> With OpenID you have only one account, your ID, which you can use
> everywhere where the OpenID technology is supported. It is not clear
> whether this setup is more secure from what we have at the moment
> (every site forces you to register unique username/password pair) but
> it is definitely more convenient.

Yes, and convenience is often the enemy of security.

> The first argument "for" OpenID is
> that the more you share your secrets, credits card information,
> usernames, password, the higher the chances this information to be
> leaked or stolen. On the other hand, OpenID is prone to phishing
> attacks so user education is required.

However, with OpenID, all I have to do is figure out how to capture your 
credentials (which does not require that I compromise OpenID), and I can 
own everything that you own.  At least with the disparate systems we have 
now you only get those things where I've been foolish enough to use the 
same credentials.  Even then you have to figure out what those systems 
are.  With OpenID I simply try every site that uses OpenID, trivial to do 
programmatically.

> Think about OpenID as the equivalent of PayPal for authentication. In
> theory, it is more secure to pay through paypal as you are not sharing
> your credit card information with everyone else but a single provider.

There's a reason I don't use Paypal......

> I am all "for" OpenID as you can spend good time on securing a single
> system. If the OpenID provider is not vulnerable to common Web attacks
> and it provides good privacy mechanisms such as SSL and the top of
> which are build good authentication features such as one-time tokens,
> etc.... then OpenID is the preferable choice.

The problem is, I have to trust the OpenID provide to both secure his/her 
systems and hire trustworthy help.  I have to do the same locally, but I 
have a great deal more control and ability to monitor.

> Keep in mind though,
> that if your OpenID account is hacked, the attacker will be able to
> login as you anywhere they want. This is the main concern and
> disadvantage.

And that is a *huge* disadvantage.

Now, there is no doubt that we need better user education.  User *must* 
learn not to trust everything they get in email.  They must also learn to 
use good passwords and not reuse them on every site they visit.  There's 
also no doubt that some sites will do a lousy job of security and end up 
exposing a person's credentials (which is why you should use different 
credentials on every site.)

We also need some sites to do a better job of requiring strong passwords. 
(Some still require only alpha-numeric characters and two few maximum 
characters.)

But the idea that SSO makes sense outside the context of a single entity 
that controls its userbase is misbegotten, in my opinion.  The individual 
*user* should control their credentials, not some "foreign" entity, no 
matter how trustworthy they may claim to be.

Paul Schmehl (pauls () utdallas edu)
Senior Information Security Analyst
The University of Texas at Dallas
http://www.utdallas.edu/ir/security/

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