Bypassing iOS 6.x Passcode Lock

According to JBN, with a sequence of moves it is possible to bypass iOS 6.x passcode lock, to directly access the address book and from here to make calls, get emails, SMS, pictures etc.

I am just curious to know if this is a planned “feature”, a back-door or just a bug and in this last case how someone managed to discover it.

The security consequences for iPhones’ owners who have their phones stolen, lost or just borrowed, should be obvious.