The hack can be accomplished by visiting the website jailbreakme.com on an iPhone, iPad or iPod touch. It is compatible with all of Apple's current iOS-powered mobile devices, including the iPad 2 and iPhone 4.
The hack was developed by "comex," Grant "chpwn" Paul and Jay "saurik" Freeman, and is compatible with iOS 4.3 through 4.3.3 on all iPads, the iPhone 3GS, GSM iPhone 4, and third- and fourth-generation iPod touch. It also works with iOS 4.2.6 through 4.2.8 for the CDMA iPhone 4.
The official site tells visitors they can jailbreak their iOS device to experience the software "fully customizable, themeable, and with every tweak you could possibly imagine." Jailbreaking is the term used to describe hacking iOS to allow users to install custom software and tweaks not approved by Apple.
The site also refers to jailbreaking as "safe and completely reversible," as users can restore their iPhone or iPad to the original, unaltered iOS software by restoring with iTunes. But jailbreaking is also a warranty-voiding process that Apple has warned users carries security risks. In 2009, a worm spread only on jailbroken iPhones that had enabled SSH for file transfer and did not change the default password.
Last July, the U.S. government affirmed that the process of jailbreaking is considered legal, though Apple is under no obligation to support users who have issues with hacked software.
The new "jailbreakme" site also asks users: "Please don't use this for piracy." While software can be legally downloaded or even sold through the jailbreak-only "Cydia" store, jailbreaking can also be used to pirate software that is sold on Apple's App Store.
This week's new jailbreak method is the second time hackers have exploited a PDF-related security hole in the Mobile Safari browser. The previous hack, issued last August, relied on a corrupt font to crash Safari's Compact Font Format handler.
Ironically, hackers who exploited the PDF security hole in iOS last year also delivered their own security fix to address the very same issue on jailbroken devices. The patch aimed to ensure that dishonest hackers would not be able to utilize the exploit for malicious purposes.