You can bypass any lockcode on an iPhone using a simple sequence of button presses. A similar iOS 4.1 bug allowed the same kind of access to the phone app. It’s not the first time a trick like this has plagued an Apple device; a similar bug was fixed with the release of 4.2 a month later. It could be a month until we see this bug is fixed, too, with iOS 6.1 coming out a month after it was fixed by Apple.”]
Source: https://gizmodo.com/ios-6-1-security-risk-anyone-can-bypass-your-iphones-l-5984190