Apple has an unfortunate history of lockscreen vulnerabilities with iOS and version 6.1 has suffered the same fate. People are finding random combinations of actions to unlock the display using emergency calling in iOS 6.1 (meaning that iPads and iPods probably aren’t affected). These actions can unlock the home screen of an iPhone running iOS 6.1 and give access to important user data.
Apple today released the iOS 6.1.3 update which apparently has a fix for this glitch as well as some map improvements for Japan in its Maps app.
For information on the security content of this update, please visit this website: http://support.apple.com/kb/HT1222.