iOS 4.3.4 is available for the iPod touch, iPad, iPad 2 and GSM iPhone 3GS and iPhone 4. GSM is the cell network technology used by many mobile phone providers around the world in including AT&T in the U.S. CDMA is used by Verizon and isn’t compatible with GSM networks, requiring Apple to release a special iPhone 4 model just for their network.
The security flaw could potentially be used to install software without user authorization, although the only in-the-wild use of the threat is the JailbreakMe hack. JailbreakMe lets users jailbreak their iOS devices without requiring a connection to a computer. Jailbreaking is a process that hacks the device so third-party apps that aren’t available through Apple’s App Store can be installed and run.
The iOS 4.3.4 update and iOS 4.2.9 update are available as free downloads. Users can install the updates by connecting their device to iTunes.