But that's exactly what researchers in Germany just disclosed, and it's raising eyebrows. The cracking technique requires attackers have physical access to the device. Considering how many mobile devices are lost every year, that's not much consolation in this case.
These researchers conducted their attack against an iPhone 4 (not jailbroken) equipped with the most recent firmware. iPads are susceptible, too. Researchers said. The passwords recovered are those used for wifi networks, some applications (depending on how they were programmed) as well as the password credentials to e-mail and VPNs.
Here's a video demonstration:
The tools and techniques needed to conduct the necessary jailbreak and file access are widely available. What this team did was figure out how to extract the actual passwords.
The researchers' full paper, Lost iPhone? Lost Passwords! Practical Consideration of iOS Device Encryption Security is available here in .pdf format.
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