writes "The technique that the Jailbreakme.com Web site is using to bypass the iPhone's security mechanisms and enable users to run unapproved apps on their phones involves exploiting two separate vulnerabilities. One of the vulnerabilities is a memory-corruption flaw that affects the way that Apple's mobile devices, including the iPad and iPod Touch, display PDFs. The second weakness is a problem in the Apple iOS kernel that gives an attacker higher privileges once his code is on a targeted device, enabling him to break out of the iOS sandbox.
The combination of the two vulnerabilities--both of which are unpatched at the moment--gives an attacker the ability to run remote code on the device and evade the security protections on the iPhone, iPad or iPod Touch. The technique became public earlier this week when the Jailbreakme.com site began hosting a set of specially crafted PDF files designed to help users jailbreak their Apple devices and load apps other than the ones approved by Apple and offered in its official App Store."Link to Original Source