The iPhone that you have been carrying has had a major security flaw uptill now, it was vulnerable to a third party attack where the hacker could capture and modify your data. The problem has been resolved by storing the missing security steps. The full security measures are detailed on Apple’s website.
Data Security Available for: iPhone 4 and later, iPod touch (5th generation), iPad 2 and later Impact: An attacker with a privileged network position may capture or modify data in sessions protected by SSL/TLS Description: Secure Transport failed to validate the authenticity of the connection. This issue was addressed by restoring missing validation steps.
Most iPhones have been using the 7.04 update till now. The 7.05 update was released exclusively for international 5S and 5C phones. However, the iOS 7.06 update is generic and is available to users as if now. Simply go to Settings->General->Update and install the new version. However Apple devices not using iOS7 will update with iOS6.16 which is applicable to fourth generation iPod and iPhones 3Gs.
Apple is also expected to launch a major update to iOS 7 this March. The update, 7.1 is speculated to make quite a few interesting changes to your phone, including a brand new dialer.