How To Hack A wi-fi Network.
WiFi or Wireless Fidelity is the name of a popular wireless networking technology that uses radio waves to provide wireless
high-speed Internet and network connections. WiFi's today are being used in every home , every office , in every Sphere of
Life.
Before hacking a wireless network you need to understand the working of wi-fi and the encryption used to secure
the connection. so lets start...
How wi-fi Works?
The working of WiFi is pretty simple to understand. The components of wireless network includes a communication device
such as a laptop or a router and internet connection The communication device which has a wireless compatibility
( laptops )converts the data in the form of radio waves and transmits it to the router, through an antenna. The router receives
the signal and decodes it. The router sends the information to the Internet using a physical, wired Ethernet connection. The
reverse communication follows the same the router receiving information from the Internet, translating it into a radio
signals and sending it to the computer's wireless adapter.
How Are Wireless Networks Secured?
In a secured wireless connection, internet data is sent in the form of encrypted packets. These packets are encrypted with network security keys. If you somehow manage to get hold of the key for a particular wireless network you virtually have
access to the wireless internet connection.
Broadly speaking there are two main types of encryption used.
WEP (Wired Equivalent Privacy)
WEP was the First type of encryption used to secure WiFi's long ago. This is the most basic form of encryption. This has
become an unsafe option as it is vulnerable and can be cracked with relative ease. Although many people still use this
encryption and that's a good news for us.
WPA/WPA2 (Wi-Fi Protected Access)
WPA ( Wi-Fi Protected Access ) and WPA2 ( Wi-Fi Protected Access II ) are two security protocols for wireless
networks from the Wi-Fi Alliance that was developed to provide a migration from WEP.This is the more secure alternative.
WPA-2 which is the most secure encryption alternative till date. Although this can also be cracked using a wordlist if
the password is common, this is virtually uncrackable with a strong password. But these encryption can also be broken.
Hacking WEP passwords is relatively fast, so we'll focus on how to crack them by using Backtrack in this tutorial.
What Will You Need?
1.A compatible wireless adapter : This is the biggest requirement that You'll have a PC with a compatible wireless adapter
that's capable of packet injection.Check Before you Hack.
2. BackTrack 5 : live CD or installed on your PC.
3. A nearby WEP-enabledWi-Fi HotSpot : you need a nearby WEP-enabled Wi-Fi with at-least 20% signal(minimal
requirement for launching WiFi hacking apps). The better the single, More chances to get the password relatively fast.
4. Command line : you need command to crack the password.
Hacking WiFi with WEP Passwords Using Backtrack
There are several easy steps down there. Follow the steps one by one and get the password of the WEP encrypted wi-fi.
Step 1 : Install backtrack or a boot from a live CD.
step 2 : Launch Konsole,The backtrack terminal. Type the following command.
ifconfig ( your interface ) up
mine is wlan0 so my command is : ifconfig wlan0 up
To see all wireless cards connected to your system simply type iwconfig.
Step 3 : first run the following commands to change your mac address.
macchanger --mac 00:11:22:33:44:55 (your interface)
Step 4 : Then you need to put your wireless adapter into monitor mode so that it can listen to every packet in the air. Put
your WiFi Adapter on Monitor Mode by this command.
airmon-ng start (your interface)
mine is : airmon-ng start wlan0
Now a new interface mon0 will be created , You can see the new interface is in monitor mode by entering iwconfig mon0.
it is shown in the below image.
Step 5 : Run the following commands to get a list of your network interfaces.
airodump-ng mon0
Bssid shows the MAC address. CH is the channel & Cipher shows the encryption type. Now choose wep protected
network as your target.
Step 6 : Now capture what is transmitting on that network and save it in a file. file name could be anything you like. Use
the following command for this.
airodump-ng -c (channel) -w (file name to save) —bssid
(bssid) (interface)
Enter anything descriptive for (file name).
As my target is broadcasted in channel 6 and has a bssid "98:fc:11:c9:14:22" ,I give in the following commands and save
the captured data as "RHAWEP"
airodump-ng mon0 --bssid 98:fc:11:c9:14:22 -c 6 -w RHAWEP
Step 7:- Now you’ll have to capture at least 20,000 data packets to crack WEP but this method is very slow, it can take
days or even weeks to capture that many data packets. Don't worry! the next command is the solution for this.
aireplay-ng - 1 3 -a (bssid of the target ) (interface)
By this commands it will take only few minuts to captute that much data to crack the password as it make a fake
authentication with the AP.
Step 8 : Now let the technology do its work,minimize the konsole,then open a new console window. Its time to inject Arp
packets for this issue these commands in new console.
aireplay-ng -3 -b (bssid of target) -h ( Mac address of
mon0) (interface)
As we have made a fake mac address for us so use aireplay-ng -3 -b (bssid of target) -h 00:11:22:33:44:55 (interface)
Step 9 : Now we will use the patience part, Basically we want to wait until enough data has been collected to run your
crack. Watch the number in the #Data column we want it to go above 10,000, best would be to wait till it reaches around
80,000 to 90,000 packets. More the packet, less the time to crack the password.
Step 10 : Once you've collected enough data. Launch a third Konsole window and run the following to crack that data
you've collected:
aircrack-ng( name of the file you saved )
If it succeeds, The WEP key appears : "KEY FOUND". Remove the colons from the output and you’ll have your WEP
Key.
If you didn't get enough data, aircrack will fail and tell you to try again with more and you will have to start from the Step
1.