Be anonymous on wireless networks: Change your MAC!

posted on August 8th, 2006


Today we’ve got a simple tutorial about how to be more anonymous when connecting to a wireless network. Your wireless card has an unique number: The MAC address. When you connect to a wireless network, this number will show up in a so called ‘DHCP clients Table’ in the router’s configuration menu. This means that the system administrator can easily check who’s connected to the network.If he sees an unknown MAC address, the only thing he has to do is find the computer using that laptop. When the numbers match your cought.

There’s only one flaw in this system: You can change the number to any number you want. We are going to use back|track for this. Check out our wep cracking guide for more information about back|track and it’s installation. After doing that, boot it up and open a terminal window. IMPORTANT: Don’t connect to the network!

1. In the terminal, type ‘iwconfig’ without quotes and look which wireless interface you want to use. I’m going to use eth0.

2. In the same terminal, type ‘ifconfig [interface] down’. Don’t type the [ and ], just replace that with your interface’s address (in my case eth0)

3. Now we are going to change the MAC address with ‘macchanger’. Macchanger allows you to change the address to something you want (eg. 11:22:33:44:55:66) or to an address that’s possible in the real world. The first option is the funniest, but will look suspisious. That’s why it’s best to use a number from a known vendor. To do this, simply type ‘macchanger -A [interface]’. But if you really want to you can also set the number by yourself. Do this by typing ‘macchanger -m XX:XX:XX:XX:XX:XX [interface]’, replace the X’s with numbers. Last but not least you can also set a fully random mac by typing ‘macchanger -r [interface]’

4. After you did that you can connect to the wireless network and when someone asks you if it’s you on the network, just show him/her the MAC printed on you wireless card.

UPDATE: Of course it’s also possible to change your password in windows (download the program by clicking here)

One comment:

  1. B-Con said on September 18th, 2006 at 7:10 pm :

    Nice tutorial.

    I believe the last line is supposed to read “it’s also possible to change your *mac address* in windows” — at the moment it reads “password”.

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