That’s according to independent security researcher Samy Kamkar, who conducted his own very basic test to determine that using the AT&T Wi-Fi hotspots available at places like Starbucks in the U.S. could potentially pose a risk to iPhone owners. The test involved trying to fake an AT&T network in order to prompt an iPhone to join a network that was potentially unsafe.

Surprisingly, the network name alone was enough to convince an iPhone that it was joining a trusted network. Kamkar merely renamed his own unsecured Wi-Fi network “attwifi.” The exploit is unique to the AT&T hotspots because generally, the iPhone looks for a MAC address and a name in order to verify that a user has been previously connected. In the case of free AT&T hotspots, however, the phone ignores the MAC address and depends solely on the name.

During the test, Kamkar’s own iPhone connected without prompting to the network, but more tellingly, at least two other iPhone or iPod touches also connected, apparently belonging to passers by or other nearby residents. By way of these unsolicited connections, Kamkar said he could do any number of things, from redirecting connected users, to stealing their login credentials.

To prove it’s possible to hijack someone’s phone using this method, Kamkar wrote a program that displays messages when a user attempts to use the Google Maps app. He’ll be releasing the program for all via his Twitter account today.

Considering that the iPhone is only officially available on AT&T in the U.S., and that most of those subscribers have probably at one time or another made use of free Wi-Fi hotspots from that provider, the security risk posed by the exploit could potentially be quite large. Especially now that the iPad, Cupertino’s rising star, is also a potential target. Apple doesn’t seem to be in a hurry to change anything about the arrangement, according to a spokewoman for the company:

iPhone performs properly as a Wi-Fi device to automatically join known networks. Customers can also choose to select to ‘Forget This Network’ after using a hot spot so the iPhone doesn’t join another network of the same name automatically.

Using the ‘Forget This Network’ function or just turning off your wireless altogether are currently the only ways to prevent your iPhone from automatically joining any network called “attwifi” if you’re concerned about the safety of your data.

Wayport, Inc., an Austin, Texas-based company, opened its doors in 1996. They initially focused on bringing Wi-Fi access to business travelers, and their early clientele included hotels and airports. In 2004, they became a provider of choice for McDonald’s, which resulted in the creation of 10,000 hotspots at the chain’s fast food restaurants in the U.S. A recent deal saw Wayport extending access at all their locations to Nintendo DS users, and it’ll be interesting to see if AT&T maintains this relationship.

The acquisition is great news for iPhone subscribers, since AT&T recently announced that all their Wi-Fi hotspots would be accessible to iPhone users free of charge. AT&T subscribers now have access to more than 80,000 access points.

It’s also an indication that the telecom giant is serious about building out their wireless infrastructure. The demand placed on their existing network by the influx of iPhone 3G users has provided headaches for AT&T in the past, and their are a couple fixes available to them. First, they can spend on new build. More 3G towers in more places, providing wider and deeper coverage. Second, they can alleviate the burden to their existing hi-speed network. Encouraging iPhone users to switch off 3G and switch on Wi-Fi eases their overall bandwidth load. And acquisitions like Wayport are a smart move in tough economic times, when companies with cash on hand can pick up smaller firms at deep discounts. If AT&T is serious about providing true blanket Wi-Fi coverage, look for them to make a move on bigger players like Boingo as the slump continues.

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