"The iPhone's security flaws were laid bare at the Black Hat Conference in Las Vegas yesterday, and now the smartphone-clutching public has boiled itself into a frenzy. But how serious is this supposed iPhone virus, and what can be done to protect your iPhone from infection? Here is what we know, and why you probably shouldn't worry.
The Attack Comes Through SMS
The iPhone virus exploits a memory corruption bug in the way the iPhone handles SMS messages. If your phone is the target of a hacker, you will receive a text message with only a square in the message -- that's when you know someone is digging his heels into your sand. But according to Eric Everson, founder of security firm MyMobiSafe, it takes a total of 512 text messages to actually get under the hood. The other 511 may float in like ghosts, totally undetectable to the user, but if at least one of them is deleted, the hack is incomplete. Turning your iPhone off or sliding it into Airplane Mode are quick and simple ways to escape the bull's-eye."
UPDATE: You can now download the fix for this from iTunes