Hackers, neighbors can intercept signals

Got a wireless home computer network? Careful you don't get whacked in a drive-by hacking.

Such wireless networks are popular because they allow everybody in the house to share a single Internet connection, printer or just about anything else connected to the system. And it all happens without cables, which means you can answer e-mail while sitting out in the back yard with your laptop.

Not all wireless network tapping is so innocent. When it's done on purpose, it's called wireless hacking, or whacking. Some refer to it as drive-by hacking or war driving, a twist on war dialing, an old hacker practice of using a computer to call every number in the book to find vulnerable dial-up computer systems.

With war driving, malicious hackers grab their laptops, jump in their cars and drive around town until the networking software on their computers picks up wayward signals from either home or business wireless networks.

Once identified, the wireless networks can be tested for vulnerability and, if accessible, used for any number of purposes.

While not an entirely new computer security threat, whacking is a fast-growing problem, thanks to the exploding popularity of wireless computing and communications equipment that use the networking standard known as 802.11b. The Wall Street Journal recently noted that 6.2 million wireless devices would be shipped worldwide in 2001 and double that by 2003.

Although some experts downplay the risk of getting whacked, others say the problem is rampant.

"For the majority of users, it's probably already happened," said Peter Shipley, a Bay Area computer security consultant. "I think the majority of people out there with wireless networks probably already have had people using them."

Shipley and others have spent a lot of effort trying to alert individuals and corporations to the risks involved with wireless networks. A few months ago, for example, Shipley proved how widespread the problem really is by taking a drive around Silicon Valley and within 90 minutes identifying more than 40 vulnerable corporate networks.

The situation for home users, Shipley said, "is very much the same, if not worse."

Shipley said virtually all wireless home networking systems using the 802.11b standard are vulnerable. And what few measures can be taken to plug wireless network security holes usually require a level of computer sophistication well above that of the average home user.

What's worse, he said, is that getting whacked can put a malicious hacker inside whatever minimal security is provided by standard personal firewall software. And once inside, the malicious hacker can do anything, from simple scanning of your files to sending out hate e-mail to government officials.

"I could send out threatening letters to the president, and you're the one who's going to get a knock on the door by the FBI," Shipley said. "The liability is going to be greater. And you're not going to have a bunch of corporate lawyers to back you up."

Shipley and others don't expect people to swear off using wireless home networks, but say they should know all that's involved with setting up such systems.

"I wouldn't say it's dangerous," Shipley said. "But you should be aware of the concerns. It's like driving a car."