Apple has released iOS 4.02 which addresses a critical security vulnerability which can allow a web page to gain control over Apple portable devices.
The update is recommended for the iPhone 4, iPhone 3GS, iPhone 3G, and iPod Touch 2nd and 3rd generations and is available through iTunes immediately. The patch may take some time to download since the iPhone version is 450MB and the iPad version 375MB. It seems Apple hasn't quite worked out how to patch the OS rather than providing a full image.
The update will reinstate the default security condition on Apple devices and thus reverse any jailbreak already performed. Besides jailbreaking, the security vulnerability is important because it can allow hackers to to break out of the Apple "sandbox" and perform any action such as stealing personal information.
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