It is good to see some analysis turning up on the exploit front. I was (and still am) surprised that the coverage of this jailbreak has been focused almost exclusively on the jailbreak itself rather than the attack vector and its implications.

The fact that a zero-day remote code execution exploit can be triggered so reliably in every iOS 4 and iPad 3.x device that the creators could drop a cute "Slide to Jailbreak" widget on a web page is alarming. With nothing more than a single rogue link and a bit of Objective C, this exploit could easily be used to produce a worm spread by e-mail or SMS to every contact with a link to the same rogue code, hopping from device to device as users tap an innocent link from a friend. In fact, the action of clicking a link could be bypassed entirely by script injection -- resulting in infection should the user merely browse to a page serving the rouge JS. Considering that the exploit is PDF-based, it's likely that it could also be triggered by viewing a document in Mail.

The prospect of iOS worms is very real, and unless Apple begins to take security more seriously (note that this is the second remote code execution exploit accessible from within MobileSafari, and they've yet to even make a peep about this one), I would not be surprised if we begin to see malware on the platform.

[ See the original exploit teardown here: http://digdog.tumblr.com/post/894317027/jailbreak-with-pdf-f... ]