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Re: Python ssl handling could be better...
From: bk <chort0 () gmail com>
Date: Wed, 2 Mar 2011 09:52:40 -0800

On Mar 2, 2011, at 6:23 AM, Charles Morris wrote:

BTW there really isn't a security difference between encrypted-but-unauthenticated traffic and just plain 
unencrypted traffic.  The only "attacker" you're defeating is a casual observer,

Fail. I hear the blackhats cackle as you switch to telnet. <snip a bunch of rambling that basically just says "MITM 
is hard">

It's hard to do if you're starting from zero and have to write your own tools.  It's not hard to do when you can just 
download something off the Internet, which is the reality we're dealing with.  Jay Beale released a tool to do this 
years ago at Toorcon.  There are many others.  Game over on that discussion.

Organized MITM by governments and backbone providers? A resounding YES
this is an issue.
MITM by disgruntled employee X or blackhat trudy? Not so much.

We should be designing systems for a high level of assurance, not "a little bit better than awful."  Besides, with the 
speed at which technology moves and the innovativeness of users, products should be made robust so they can stand up to 
unanticipated usage.  For example, if someone went out and wrote a Twitter client based on python-twitter and it became 
popular in North Africa, many people would falsely think their revolutionary conversations are "secure" because it 
"uses SSL", but in fact the oppressive governments can trivially sniff all the traffic (and possibly impersonate 
trusted users?).

An attacker who is motivated to cause harm will find the tools to do what they want, so MITM is not a high bar.  There 
are available tools to do it that don't require expertise.  As I said previously, the only attacker defeated by 
unauthenticated SSL is the one who wasn't going to cause much harm any way.

Maybe it's even worse than pointless.

It's the idiot user's fault if they don't understand the difference

Ahh yes, the chorus of nerds everywhere.  Guess what, most people just do their job, that they're good at, and expect 
the technology to do the right thing.  The assume computer professionals are as thoughtful about making things easy to 
use and safe as the designers of microwaves, lawn mowers, paper shredders, etc...  With those things you have to try 
really hard to hurt yourself or cause damage.  With unsafe SSL you're hurting yourself by default.  That would be akin 
to a microwave melting your eyes if you were "too stupid to wrap the appliance in protective shielding."

In short-
Encryption without authentication is ALWAYS BETTER than no encryption

It's not.  Would you like to jump out of an airplane with a parachute that you THINK will work, but doesn't, or one 
that actually will work?  You'd make a different choice if you knew the chute wouldn't open.

Authentication without encryption is ALWAYS BETTER than no authentication

Not if it can be captured/replayed to impersonate you in the future. WTF are you smoking?

Encryption with authentication is ALWAYS BETTER than either of the
above two scenarios

Even a broken clock...


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