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Imagine a car equipped with nothing but a laptop, a portable GPS receiver, and a wireless network card slowly cruising through your neighborhood. Unknown to onlookers, this is no ordinary vehicle; rather, it is a driving machine. As the car passes through homes and businesses, a wireless network card (available at any electronics store for as little as $ 25) searches for any wireless access point. Anyone with a wireless network (and there are many) is vulnerable. The computer is looking for what is called the SSID. An SSID is the name of your wireless network and is constantly broadcast by your access point, informing computers of its presence. Wardriver uses software like Netstumbler (for Windows) or Cismet (for Linux) to scan radio waves for SSIDs. The program can track multiple access points at once and monitor signal strength. These programs can also verify if the network is encrypted. The Wardriver will generally configure its software to record any strong unencrypted signals. Using the GPS receiver, the coordinates of the strong signal will be recorded. After this preliminary trip, the driver on duty can return to the locations that were registered and connect to the access point. Once connected to an unencrypted network, the driver on duty can use the victim’s Internet access and can also explore computers on the network. If the files are shared within someone’s private network, all that information is subject to a gatekeeper. Additionally, once on the network, a controller can track network traffic and can view any information such as passwords and credit card numbers that you send to the Internet, including SSL-protected data. The vulnerability of wireless networks is a major problem, and as more and more households purchase wireless technology, the problem of insecure networks increases. Sounds scary? Well, this happens every day and you don’t have to be an expert to do it. However, you don’t need an expert to protect yourself.
Steps you can take to protect yourself against on-call drivers:
There are a number of very simple steps you can take to protect your wireless network. For many of these, you will have to access your router’s configuration utility (see your manual on how to do this, you will generally need to type an IP address into your browser, such as 192.168.0.1 or 192.168.1.1).
Do not broadcast your SSID. If you are broadcasting your SSID, this is the first thing a program will pick up on and recognize. If you configure your router not to broadcast its SSID, it will be difficult to detect (but not impossible, as some software can detect wireless communication, so if you are using your wireless network, the SSID may be revealed). If you’re not broadcasting your SSID, but you can guess it (for example, you’re using a default SSID), cloaking doesn’t make sense. Because of this, remember to change your SSID from the factory default. This is not a 100 percent effective method of protecting your network, but it is a good first line of defense.
Change the default password. When you buy a router, a factory password is stored. People with experience working with routers know the default passwords for different routers (and wardriver software like netstumbler can see the brand of the router). It is important that you secure your router with a good password.
Encrypt your wireless communication. I cannot stress enough the importance of encrypting your wireless communication. Enable encryption and enter a key. Most routers are only capable of encrypting WEP, but if they allow it, use EAP encryption, it is more secure than WEP. Like hiding your SSID, encryption is not 100% secure. With enough time and determination, if someone wants to target you and access your network, WEP encryption can be bypassed using software like AirSnort.
Filter the MAC addresses that can connect to your router. This would require you to enter your router settings and enter the MAC address of each wireless card you have. This will restrict access so that only your computers can connect to the router. You will need to obtain the MAC address (which is the individual identification address of a network card in the form of a 12-digit hexadecimal number). If someone tracks traffic and detects a computer’s MAC address wirelessly using your network, the driver could emulate that address and connect to the router, but this takes time.
If you set up file sharing on your computers, make sure it is password protected. You should not share files on your networked computers unless you require an authenticated user to access. Set up the same user accounts on your machines so that your computers can share files.
With these relatively simple steps, wireless network users can protect their networks from controllers. Wireless networks are inherently insecure, and these tips will simply help you protect your network. If someone is really determined to gain access to your network, given enough time, a good hacker can gain access. However, these tips will deter the average user from accessing your network. Although these methods are not definitive security measures, they will change your network from something that can be hacked in a matter of seconds, to something that will take a hacker days, if not weeks of work, all of which will have to be done. while in close proximity to your network.