A security flaw that enabled the lock screen on the iPhone 4, specifically iOS 4.1, to be bypassed via the emergency call button has been fixed with the update to iOS 4.2.

The flaw in iOS 4.1 showed itself through a video of a man bypassing the pass-code protected lock by first pressing the emergency lock followed by three ###, whereby a tap of the green button and an immediate press of the off button on the top of the phone gave a degree of access to the handset.

The information available included voicemail, call history and the address book; all other functions were left secure.

However, BGR has now reporting that the iOS 4.2 gold master candidate closes the security issue saying: "We’ve been trying, unsuccessful[ly], to replicate the issue with the latest iOS pre-release".

Watch this space for the full release of iOS 4.2 in the coming weeks.

-iOS 4.2 SDK now available