Re: "The End of SSL and SSH?"

[Samuele Giovanni Tonon <tonon () STUDENTS CS UNIBO IT>]

On Wed, Dec 20, 2000 at 09:01:48PM -0700, Kurt Seifried wrote:
> People (ie the masses of users, you know, the people you support/etc) generally know a LOT less about security then 
> your average
> Bugtraq subscriber.
>
> They by and large believe that SSL and SSH are "secure". I've had countless websites say "we are secure because we 
> use SSL". Well I
> think we all know better.

that's a good point of view but if you use this point  of view for all
security aspects you have in informatic and in "real-life", ( e.g. your passwd on the ISP account
or your pin of the C.C. or the pin of your cell phone ) you'll find there's no
"secure protocol" against human stupidity/ignorance ( when all fails
social engeneering works !).
> The main point of the article was to let people know that SSL and SSH are far from perfect, in fact I think they are 
> pretty poor
> because they rely so heavily on the end user (usually the weakest link).

you can extend this discussion to all modern crypto protocols: none seems to
work against man in the middle attack or against simulating to be a man you
aren't.

> This wasn't to much of a problem till recently because the
> availability of software to execute a man in the middle attack was not to widespread. Well Dug Song changed all that 
> with dsniff
> 2.3. Attackers now have to know very little to execute an attack, and in many situations they probably stand a good 
> chance of
> succeding.

this is true if you think just to script-kiddie, every good programmer could
do it, without telling others he did it, and use his program to spoof a lot of
account.
what dsniff do is to extend the number of potential attaccker to script-kiddie
too: but now, all of us are warned when ssh says : hey there's a new public key
.

> People have mentioned /etc/hosts and known_hosts. Well tiny problem, there's this desktop OS called Windows that has 
> like 95% of the
> market and as a rule of thumb the hosts file in Windows is usually non existent (as a rule the only entry by default 
> is localhost).

that's not the point: if you were using ssh on windows but you were trojaned
by netbus the attacker could just see what you were typing on your keyboard,
so ssh is  far to be secure if it's used on a insecure OS .

> We can move the problem "back" for example by using certificates for example, in theory if I create an X.509 cert 
> properly on my
> smartcard, and Verisign doesn't goof up on checking my identity then that X.509 cert is pretty secure, and now when I 
> connect to
> sites capable of taking an X.509 cert as auth it's pretty safe.

how many "dummy user" do you think they'll do this when it will be avaible ?
none seems to check if the cert you get from a https server is right ... do
you think there won't a way to steal and clone your smart card ??

Sorry for my ugly english

Samuele

--

Samuele Tonon <tonon () students cs unibo it>
Undergraduate Student  of  Computer Science at  University of Bologna, Italy
Linux System administrator at  Computer Science Research Labs of University
of Bologna, Italy

Founder & Member of A.A.H.T.