Experts last week showed how to put together a wireless hacking kit for less than £1,200.
Speaking at NetEvents, Jan Guldentops, director of Better Access Labs, demonstrated how a hacker could create the kit using "any old laptop, an antenna, GPS, power unit and software. And the entire thing fits in a briefcase."
Guldentops said the advent of a wireless standard meant it was easy for external hackers to access the wireless Lan.
"I spent two weeks in Belgium just driving round looking for open wireless networks. I found 263 and was able to connect to 85 per cent of these immediately," he said.
Those with zero security included "banks, police offices, and Belgium's biggest brewery."
Caelen King, marketing manager of Baltimore, speaking on the NetEvents panel, said: "Any wireless device is an access point into your network, potentially even wireless-equipped soda machines."
Guldentops said that companies need to learn how to secure an inherently insecure environment. He said it is relatively easy to make wireless access points more secure, either by using Wired Equivalent Privacy encryption protocol, or configuring it to drop unencrypted packets, effectively making it invisible.
"Some of these companies are just using antennas that are too powerful," he said. "Some are almost big enough to be radio stations."
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