Apple probably spent most of the time patching the evasi0n exploits and missed this security flaw.
It was just a few weeks ago when the same type of exploits were discovered in iOS 6.1. Apple was quick to patch them but when iOS 6.1.3 was released yesterday, a similar flaw was discovered by this guy.
The good news is that only iPhone 4 is only affected by this issue. The key method of bypassing your iPhone 4 is by using the Voice Control feature.
By following the steps shown in the YouTube video below, the intruder can view your address book and pictures without the need to enter your passcode.
The person who discovered this flaw recommends iPhone 4 users to disable Voice Control until a fix is available.
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