There’s a security flaw to be aware of with iOS 5.0.1 which allows someone to bypass the lock screen on GSM-based iPhones and have unauthorized access to contacts as well as the phone’s calling features.
The method used is admittedly fairly complicated and involves inserting and ejecting the phone’s SIM card a number of times as a part of the process, as well as making several missed calls to the phone (which also means the attacker needs to know the victim’s phone number).
Providing the hack is executed correctly and multiple deliberate attempts are made to return a missed call without the SIM card (or any network coverage), the iPhone will unlock itself straight to the Phone application, in which the SIM card can then be re-inserted and leaves the contact list exposed as well as the ability to make FaceTime calls etc.
You can get a better idea of what it takes to accomplish the hack in the video demonstration below.
KitGuru says: We are not sure if Apple is already aware of this flaw, but in any case we’d expect it will be addressed in time for the release of iOS 5.1 which is still currently undergoing developer testing.