We live in a world of open and I mean wide open 10:42 networks we could go to an airport and find an
open network we can go to a coffee shop and find an open network we can go almost anywhere and find
an open network now.
That's kind of a good thing because it provides us instantaneous and easy access to the Internet which
is maybe why we're doing this and there's no other really easy practical way to handle that other than
passing everybody out.
Pre-shared keys are giving everybody usernames and passwords on 8:0 2.1.
So the bottom line is is we live in a world of open networks.
The problem with this is open networks by definition are absolutely wide open.
Now to show you how bad the problem is.
I've got a little setup here.
So what I have here is a little home router This is a little aces 8 to 11 Acey home router.
Very popular I use these in all my courses over here I've got my windows 10 laptop he's just a regular
laptop nothing special.
And he is connected to a wireless network called simple which is being passed out by this guy and over
here I've got my Linux system I'm running colleague Linux with a whole bunch of toys up and running
and I'm using a very special wireless network card that is designed to allow us to be able to go into
a promiscuous mode to get out there and monitor what's going on in the network and we can do all kinds
of fun stuff like this.
So with this little set up in mind one of the things you need to understand first and foremost is anything
that I'm doing on here unless very specific things are done on an open network.
I can see it all over here.
Now here I have Cali Linux running over on this system and what you're looking at is all the data that
I've captured off this wireless network.
Don't look too close.
Kids I didn't give you anything that you can actually do any danger to me with.
So being able to just capture data is fairly trivial.
Now of course you'd have to be good at Wireshark.
You'd have to know how to follow TCAP streams and be able to look for different types of data searching
for HTP searching for someone being silly enough to check their email insecurely do something like that.
But if you're comfortable with wireshark you've basically got keys to the kingdom and you look at anything
you want.
So in and of itself that's already bad.
But I can make it worse.
One of the problems we run into is the idea of using cookies for sessions so I could go up to a particular
Web site and I will create a session cookie that will exist during the length of whatever session I
might have.
Now the session cookies hold different types of information and a lot of times especially if you're
typing in user names and passwords.
What will happen is this website will go to HTP S and you type in your username and password securely
which I'm not going to be able to do anything with.
But then the server is going to pass down a cookie which gives your authentication information in it.
So this can be a big problem.
So one of the tools we can use is for example what I have over here is a wonderful tool called kooking
Cadger cookie Cadger only has one job.
He looks out to anybody who's passing out just cookies just HGP cookies that's all he's looking for
and he grabs them and he brings them down into the system.
And if I want to I can go ahead and do something called a replay attack with these.
Let me show you how this works.
Here is my happy little victim computer merely logging onto the Internet onto some u r l that is in
Cicare so we'll call it some very insecure sounding name.
Now a lot of times when people log in if they're typing in usernames and passwords a lot of Web sites
will shift.
HTP.
As for the actual authentication of that particular system.
So this is done in such a way that it's encrypted.
Nobody can get to it.
However a lot of times after this is done some form of cookie holding authentication information is
held on the victim computer.
Now us using our evil computer over here we can use tools like cookie Cadger to intercept the actual
cookies the cookies themselves are not sent over secure they're sent over insecure.
Only the actual log on itself was.
So we can grab this make a copy for ourselves.
And even after the victim leaves we can go ahead and use the authentication information in this cookie
to in essence replay just as though we were the original victim ourselves.
And that is a classic replay attack.
So what do we do to protect ourselves what can we do on our good computers to prevent these bad computers
from sniffing our networks.
What do we do to keep these bad guys using tools like cookie Cadger from grabbing our cookies and taking
out all that SSL information and using it against us in these replay attack which by the way is also
known as SSL stripping so be comfortable with that term.
So what can we do.
Well there's a lot of things you can do.
Number one use secure protocols when you're on insecure wireless networks if you're going to be doing
FGP you secure FGP if you're going to be getting e-mail you secure e-mail do what you can to be secure.
In particular though I want to concentrate on HTP s because well people use the web a lot so I want
to talk about in particular some of the things we can do.
Number one what I'd like you to do is that you need to watch your browser bar so if you take a look
up here you can see right here I'm on a secure Web site.
Of course it says a TTP Yes but it also shows very very clearly secure.
Now over here is a very insecure web site.
This is my own web site.
Trust me if you try to buy something online we go very very secure.
But at this point it is insecure.
So you need to be able to have the wherewithal to think about what are you doing on a particular site
you might be on just one particular Web site but it can pop from HTP to HTP.
If you're insecure you probably don't want to be typing in usernames and passwords on that particular
page.
Now the problem is as security people we can think this much about it.
Unfortunately users don't.
So we need tools to help them make sure they're always in a secure environment.
One of the great tools we use and I use this in Chrome all the time is something called HTP s everywhere.
So if you take a look right up here you'll see I've added a little extension called HTP everywhere.
And what I'm going to do is I'm going to turn it on by blocking all unencrypted requests.
Now right now you'll see that I'm on a secure Web site.
Watch what happens when I go back in.
You'll see that it's popped instantly to a secure w w w dot total some dot com and that's the power
of HDTV as in fact making people use HTP is so critical that even the industry has developed protocols
where servers require your browser to go to HTP.
This is known as HTP strict transport security or h s ts in it is a beautiful thing it pretty much auto
magically does what HTP everywhere does for you.
So it's a very very powerful tool but only on servers that actually use it.
So between h s ts and HTP everywhere and watching the little green bar at the top I'm pretty safe from
bad guys doing naughty things.
Now there's one more thing I'd like to add.
NET is a VPN.
If you really want to be secure what you do is get on the Internet but have everything go through a
VPN they got to be careful here.
You could have a corporate VPN where you Dayalan to the Internet and get online for your corporate stuff
and that's great.
But a lot of corporations will set up a VPN not for you to just access the internal network but as a
tool that makes sure all the corporate computers when they're at airports or when they're in some foreign
country with open networks can be guaranteed that anything's machines do allows them to do it through
the VPN.
Even just general browsing.
Now you've got to be careful with this.
I want to show you some VPN.
And again I'm doing this and chrome
if you go through you'll see that there's a lot of extensions that are offered in Chrome and in no way
am I going to offer any of these up to you these different proxies.
The problem with these V-P ends is that while they're free so anytime something's free that means you're
the product so they tend to look at information you may not want them to.
Also these VPN that you'll see are often used by bad guys that what they'll do with the VPN is that
they can set the VPN so they come out in the UK if they want to watch Manchester United are some soccer
team.
So there is a bit of a nefarious side to using these VPN as well as a very good aspect of it.
And that is simply using it to prevent bad guys from doing things in open networks.
So there you go we've got a number of different tools for you.
You're going to be seeing a lot of this on the exam.
So take some time and be comfortable.
You can do to protect yourself on open networks.