Prolific iOS hacker pod2G has released to jail breakers a new exploit, which for the first time brings a homogenous and simple jailbreak for iOS 5 devices.
The jailbreak has been incorporated into redsn0w, the most popular jailbreak tool, and supports all devices with the exception of Apple A5-toting iPad 2 and iPhone 4S. This is due to the exploit depending on an ARM exploit in both the Samsung CPUs powering iPod touch 3G and iPhone 3GS, as well as Apple’s A4 processor.
pod2G believes that the same exploit could be carried over to Apple’s A5 processor, but will require additional work, as it is a very low-level exploit. Also significant is that this untethered jailbreak functions on both GSM and CDMA variants of the iPhone 4.
iOS 5 marked additional efforts to thwart jailbreakers by Apple. The devices now require two-way activation, meaning the firmware update bundles must both “phone home” to Apple for approval codes, and then “phone back” with confirmation codes that the update bundle was not tampered with. Previously users could downgrade iOS versions by spoofing Apple’s activation server, and backing up the “phone home” codes (commonly referred to as SHSH or ECID numbers).
The jailbreaking community has been largely fractured at this point, with the number of apps and working jailbreak programs drying up. Apple’s efforts have been effective in creating jailbreak fragmentation; some users are still using iOS 4.2.1 (jailbroken), some are running iOS 5 (in a tethered jailbreak), and a significant number have simply moved on and no longer jailbreak.
With the release of the iOS 5.0.1 untethered jailbreak, the jailbreaking community will finally be unified on a single version, albeit with a smaller community pool. It remains to be seen how vibrant the jailbreaking community will thrive, as Apple appears to remain committed to a walled garden approach, despite jailbreakers presenting many valid and functional applications that justify the practice.