A hacker has exploited the vulnerability of iOS 5 by hacking into the newly launched, but not yet released, mobile operating system.

iOS 5, which generated a lot of excitement during its launch on the opening day of the Apple's Worldwide Developers Conference (WWDC) 2011, is one of the most important software advancements made by the technology giant.

iOS 5 reportedly comes with 1500 APIs and 200 new features. The ten most important features that promise to help the next generation iPhone beat rival Android were presented on the opening day of WWDC 2011. Some of them are Delta Updates, iMessages and improved Notifications.

A member of the iPhone Dev Team revealed through Twitter that iOS 5 was susceptible to an exploit, limera 1n, which targets a vulnerability in the iOS 5 boot software.

MuscleNerd, who pointed out this matter describing himself as 'iPhone hacker' on his twitter profile, said iOS 5 jailbroken on ipt4g ... via limera1n + tethered boot on his tweet. He also posted two photos of the jailbreak OS 5, with one of them showing iPhone's home screen as the proof.

Apple said it plans to release a final version of iOS 5 this Fall.