Basic Entry into a WEP Encrypted Network
I
know that many people have thrown up various tutorials before about
hacking wep with Backtrack 3 but I never felt that they fully explained
everything very well for noobs. (at least not the ones I read) This is
in no way meant to attack someone else that has posted a tut on this
before...I simply wanted to put one up that was very easy to follow even
if you had never done anything like this before. Since this explains
EVERYTHING in detail, it is quite long. Enjoy.
1. Getting the right tools
Download Backtrack 3. It can be found here:
Code:
2. Preparing the victim network for attack
Once
in BT3, click the tiny black box in the lower left corner to load up a
"Konsole" window. Now we must prep your wireless card.
Type:
Quote:
airmon-ng
You will see the name of your wireless card. (mine is named "ath0") From here on out, replace "ath0" with the name of your card.
Now type:
Quote:
airmon-ng stop ath0
then type:
Quote:
ifconfig wifi0 down
then:
Quote:
macchanger --mac 00:11:22:33:44:55 wifi0
then:
Quote:
airmon-ng start wifi0
What
these steps did was to spoof (fake) your mac address so that JUST IN
CASE your computeris discovered by someone as you are breaking in, they
will not see your REAL mac address. Moving on...
Now it's time to discover some networks to break into.
Type:
Quote:
airodump-ng ath0
Now
you will see a list of wireless networks start to populate. Some will
have a better signal than others and it is a good idea to pick one that
has a decent signal otherwise it will take forever to crack or you may
not be able to crack it at all.
Once you see the network that you want to crack, do this:
Quote:
hold down ctrl and tap c
This will stop airodump from populating networks and will freeze the screen so that you can see the info that you need.
**Now
from here on out, when I tell you to type a command, you need to
replace whatever is in parenthesis with what I tell you to from your
screen. For example: if i say to type:
Quote:
-c (channel)
then dont actually type in
-c (channel)
Instead, replace that with whatever the channel number is...so, for example you would type:
-c 6
Can't be much clearer than that...lets continue...
Now
find the network that you want to crack and MAKE SURE that it says the
encryption for that network is WEP. If it says WPA or any variation of
WPA then move on...you can still crack WPA with backtrack and some other
tools but it is a whole other ball game and you need to *** WEP first.
Image
Once you've decided on a network, take note of its channel number and bssid. The bssid will look something like this --> 05:gk:30:fo:s9:2n
The Channel number will be under a heading that says "CH".
Now, in the same Konsole window, type:
Quote:
airodump-ng -c (channel) -w (file name) --bssid (bssid) ath0
the
FILE NAME can be whatever you want. This is simply the place that
airodump is going to store the packets of info that you receive to later
crack. You don't even put in an extension...just pick a random word
that you will remember. I usually make mine "wepkey" because I can
always remember it.
Quote:
**Side
Note: if you crack more than one network in the same session, you must
have different file names for each one or it won't work. I usually just
name them wepkey1, wepkey2, etc.
Once
you typed in that last command, the screen of airodump will change and
start to show your computer gathering packets. You will also see a
heading marked "IV" with a number underneath it. This stands for
"Initialization Vector" but in noob terms all this means is "packets of
info that contain clues to the password." Once you gain a minimum of
5,000 of these IV's, you can try to crack the password. I've cracked
some right at 5,000 and others have taken over 60,000. It just depends
on how long and difficult they made the password.
Now
you are thinking, "I'm screwed because my IV's are going up really
slowly." Well, don't worry, now we are going to trick the router into
giving us HUNDREDS of IV's per second.
3. Actually cracking the WEP password
Now leave this Konsole window up and running and open up a 2nd Konsole window. In this one type:
Quote:
aireplay-ng -1 0 -a (bssid) -h 00:11:22:33:44:55 ath0
This
will send some commands to the router that basically cause it to
associate with your computer even though you are not officially
connected with the password. If this command is successful, you should
see about 4 lines of text print out with the last one saying something
similar to "Association Successful :-)" If this happens, then good! You
are almost there. Now type:
Quote:
aireplay-ng -3 -b (bssid) -h 00:11:22:33:44:55 ath0
This
will generate a bunch of text and then you will see a line where your
computer is gathering a bunch of packets and waiting on ARP and ACK.
Don't worry about what these mean...just know that these are your meal
tickets. Now you just sit and wait. Once your computer finally gathers
an ARP request, it will send it back to the router and begin to generate
hundreds of ARP and ACK per second. Sometimes this starts to happen
within seconds...sometimes you have to wait up to a few minutes. Just be
patient. When it finally does happen, switch back to your first Konsole
window and you should see the number underneath the IV starting to rise
rapidly. This is great! It means you are almost finished! When this
number reaches AT LEAST 5,000 then you can start your password crack. It
will probably take more than this but I always start my password
cracking at 5,000 just in case they have a really weak password.
Now you need to open up a 3rd and final Konsole window. This will be where we actually crack the password.
Type:
Quote:
aircrack-ng -b (bssid) (filename)-01.cap
Remember
the filename you made up earlier? Mine was "wepkey". Don't put a space
in between it and -01.cap here. Type it as you see it. So for me, I
would type wepkey-01.cap
Once
you have done this you will see aircrack fire up and begin to crack the
password. typically you have to wait for more like 10,000 to 20,000
IV's before it will crack. If this is the case, aircrack will test what
you've got so far and then it will say something like "not enough IV's.
Retry at 10,000." DON'T DO ANYTHING! It will stay running...it is just
letting you know that it is on pause until more IV's are gathered. Once
you pass the 10,000 mark it will automatically fire up again and try to
crack it. If this fails it will say "not enough IV's. Retry at 15,000."
and so on until it finally gets it.
If
you do everything correctly up to this point, before too long you will
have the password! now if the password looks goofy, dont worry, it will
still work. some passwords are saved in ASCII format, in which case,
aircrack will show you exactly what characters they typed in for their
password. Sometimes, though, the password is saved in HEX format in
which case the computer will show you the HEX encryption of the
password. It doesn't matter either way, because you can type in either
one and it will connect you to the network.
Take
note, though, that the password will always be displayed in aircrack
with a colon after every 2 characters. So for instance if the password
was "secret", it would be displayed as:
Quote:
se:cr:et
This would obviously be the ASCII format. If it was a HEX encrypted password that was something like "0FKW9427VF" then it would still display as:
Quote:
0F:KW:94:27:VF
Just
omit the colons from the password, boot back into whatever operating
system you use, try to connect to the network and type in the password
without the colons and presto! You are in!
It
may seem like a lot to deal with if you have never done it, but after a
few successful attempts, you will get very quick with it. If I am near a
WEP encrypted router with a good signal, I can often crack the password
in just a couple of minutes.
I
am not responsible for what you do with this information. Any
malicious/illegal activity that you do, falls completely on you
because...technically...this is just for you to test the security of
your own network. :-)
I will gladly answer any legitimate questions anyone has to the best of my ability.
. No one wants to hold your hand through this...read the tut and go experiment until you get it right.
There
are rare occasions where someone will use WEP encryption with SKA as
well. (Shared Key Authentication) If this is the case, additional steps
are needed to associate with the router and therefore, the steps I lined
out here will not work. I've only seen this once or twice, though, so
you probably won't run into it. If I get motivated, I may throw up a tut
on how to crack this in the future.
