A Cambridge computer scientist has managed to achieve something in just $100 for which the FBI had to pay more than a million dollar. He managed to find a way to get unlimited attempts at guessing the passcode of a locked iPhone that eventually allowed him to unlock the phone.

Earlier this year, the FBI had said in the San Bernardino case that such an approach would not work in unlocking the iPhone 5c of one of the terrorists involved in the terrorist attack.

In a video uploaded to YouTube by Dr. Skorobogatov, he demonstrated how he was able to remove a NAND chip from an iPhone 5c, cloned it using a cheap hardware tool, and then put the clone chip back in the phone. This cloned NAND chip had its pin attempt counter set to zero so Dr. Skorobogatov could repeat the process of unlocking the phone as many times as he wanted without locking the phone. It took the computer scientist around 40 hours to unlock a locked iPhone 5c using this procedure, though it was using a four-digit passcode.

Unlocking an iPhone with a six-digit code can potentially take up to hundreds of hours though.

While it will be possible to clone NAND memory chips from newer iPhones like the iPhone 6 using more sophisticated process, more information would be required on how Apple stores data on the NAND of its newer iPhones to make the cloning process a success.