A MacRumors forum member
found a neat and slightly worrisome bug in Apple's iOS
. A simple combination of buttons, along with a good sense of timing, can completely bypass the iPhone's passcode lock screen
. To recreate it, simply tap the "emergency call" button in the bottom left-hand corner of the lock screen. Then, enter a non-emergency number. The forum member used "###," but we also had success with "666." Then, in quick succession, tap call and press the lock button. You should then see a message that the phone is ending the call, and the phone app should magically appear. The phone app provides access not only to the dial pad, but to your contacts, call history and voicemail, as well.
We had pretty solid success recreating the iPhone
code on an iPhone 3GS running iOS 4.1. Our jailbroken 3G running 4.0.1 was a little less reliable. We were booted back to the lock screen after being able to poke around the phone app for about five seconds. After the code was used once, a phone reboot was required to get it working again. According to Engadget, the exploit works flawlessly with the beta of iOS 4.2, as well. Apple
hasn't acknowledged the bug yet, and it remains to be seen whether or not it gets patched before 4.2 is released to the public.