iOS 6.1.3 has been released and you can download 6.1.3 from below links. Since there is no jailbreak available for iOS 6.1.3 we should keep away from upgrading to 6.1.3. Once we get genuine news that there is a jailbreak program available to jailbreak 6.1.3 we will update you and you can then safely upgrade to ios 6.1.3
Download iOS 6.1.3
You can download iOS 6.1.3 from below links and then upgrade using iTunes.