The latest news from Wi-Fi security vendor AirTight is that airports leak data: The folks at AirTight regularly suit up, carry Wi-Fi monitoring gear around, and report on how bad people are at securing networks--laughably, often at Wi-Fi and security conferences. Their latest bit of PR has a lot of bad news in it, worth reporting. They found that in testing across 14 U.S., Canadian, and Asian airports, that they found unsecured and WEP-protected networks on 80 percent of the visible non-public networks. They believe that some of those networks are used for logistics and operations. (They wisely didn't probe too far; they could have wound up in the pokey in some states and countries.) They scanned 478 access points.
They also found that 10 percent of the laptops they scanned--out of a total of 585 Wi-Fi clients--had an ad-hoc network in place. That's the "Free Wi-Fi" network you see whenever you're in public, which is spread by people connecting to the network, which is then advertised to other people. While the network itself may just be an artifact of Windows XP's damaged ideas about how to advertise network availability, connecting to another laptop via an ad hoc method creates the potential that any viruses you or they have will be shared.