This guide is meant to show how easy it is to hack wireless networks if the proper security measures are not in place. First I will show how to hack a WEP or WPA/WPA2 Network and then I will give tips on how to avoid getting hacked.
This is important information in our techno-savy culture. If your wireless network is compromised you can be liable for any illegal activity on it. There are numerous stories of child pornographers and black-hat hackers using other peoples wireless networks.
NOTE: Hacking your neighbors or anyone else’s Wifi without their permission is ILLEGAL. Be smart!
Step 1What you Need
-If your laptop wireless card can’t do packet injection you can purchase a wireless adapter such as the Netgear WG111 v2 for around $8-$12 on eBay.
Step 2Hack WEP
1. Boot into BackTrack
2. Click on the Backtrack applications menu -> Backtrack -> Exploitation tools -> Wireless exploitation -> WLAN Exploitation -> gerix-wifi-cracker-ng (This will open up the GUI interface seen in the picture).
3. Go to the configuration menu and select the wireless interface wlan0
-Click on Enable/Disable Monitor Mode (this will put the wireless card into monitor mode).
-Select the newly created mon0 interface.
4. Now click on the WEP tab at the top of the window.
-Click on “Start sniffing and logging” and leave the terminal open.
-Once the wireless network you want to crack* shows up (it has to be WEP encryption of course) select the WEP Attacks (with clients). *note that the PWR has to be high enough to work so the closer you can get, the better.
-There you click on “Associate with AP using fake auth”, wait a few seconds and click on “ARP request replay”.
5. Once the Data number reaches over 10,000 you are ready to try (if the data is coming fast wait until 20 or 30,000 to be safe) and crack the key, but don’t close any windows yet.
-Go to the cracking tab and click on “Aircrack-ng – Decrypt WEP password” under Wep Cracking.
It will take a few seconds to minutes to crack the password and then you are good to go.
Step 3Hack WPA/WPA2
-Open up Konsole which is a command line utility built into BackTrack. It is the Black Box in the Lower-Left Hand Corner (See Image).
We will now be entering the following commands into the command line noted by Bold as well as explanations as to what they do:
-The following commands stop the wireless interface so you can change your mac address, this is important because your mac address is a unique identifier so faking one is a good idea if you are accessing a network you don’t have permission to. (which by the way I wholly condemn)
airmon-ng stop wlan0
ifconfig wlan0 down
macchanger –mac 00:11:22:33:44:55 wlan0
airmon-ng start wlan0
-Now we will put the airodump-ng tool into monitor mode, this will allow us to see all of the wireless networks around us (See the first Picture).
Now choose the network you want to hack and take note of the BSSID, and the Channel it is one as well as the ESSID. The PWR has to be fairly high to be able to hack it, this is determined by how close you are to the wireless router. The closer you are, the better.
Once you have chosen the wireless network enter the following into the terminal:
This will write capture packets and put them into the “filename” file, we are trying to capture the handshake between the router and wireless connection which will give us the key we need to crack.
airodump-ng mon0 –channel * –bssid **:**:**:**:**:** -w filename
The following step is optional but is highly recommended as it will speed up the process a great deal.
Once “WPA handshake: **:**:**:**:**:**” appears in the top right-hand corner we can move on. If you are having trouble getting the WPA handshake to occur then do step 4.
aireplay-ng -0 1 -a **:**:**:**:**:** -c **:**:**:**:**:** mon0
What this step (4) does is it deauthorizes a wireless connection and trie to re-establish it so it will generate a new handshake to capture. This step ends once you have captured the handshake.
aircrack-ng –w wordlist.lst -b **:**:**:**:**:** filename.cap
Step 5 is now trying to crack the password in “filename.cap” using a list of words, here called “wordlist.lst” you can download a good 200 million word dictionary here (128MB but unzipped is 800MB).
Your computer has to compute the hash value of every password in that list but a computer can go through those 200 million passwords in 6-12 hours.
If the password isn’t found in the dictionary you can try and brute-force the password with this command: (Note this could take a very long time depending on their password strength).
/pentest/password/jtr/john –stdout –incremental:all | aircrack-ng -b **:**:**:**:**:** -w – filename.cap
Step 4Secure Your Own Wireless Network
2. Don’t base your password on a dictionary word. The next section focuses on passwords in general.
3. In your router settings you can usually hide your ESSID (the name of the wireless network) this will add a small layer of security.
4. In your router there is probably a mac-address filtering service where you can specify the mac addresses that are allowed to connect. This will make sure that only your approved devices can connect to your network. (obviously a problem though if you have a guest over and wants to connect to your Wifi).