Screw up enough times and your phone will erase its data.This protects your i Phone from something called a "brute-force attack," a hacking attempt in which a computer sends thousands and thousands of possible pass codes to the i Phone until it lands on the correct one.
As security researcher Dan Guido writes at Trail of Bits, only Apple has the secret keys necessary to make an i Phone accept a firmware update. The FBI's request indicates Apple could create a firmware update that would only work on the specific i Phone involved in this case.In case you haven't heard, Apple announced Tuesday that it's refusing to write code for the FBI that would unlock one of the San Bernardino shooters' i Phones. But the FBI is part of the same government as the NSA.CEO Tim Cook said in a post on the company's website that doing so could undermine security for all i Phones: The government is asking Apple to hack our own users and undermine decades of security advancements that protect our customers — including tens of millions of American citizens — from sophisticated hackers and cybercriminals. And the NSA built Stuxnet, a bit of code that wormed its way around the world to destroy air-gaped nuclear machinery in Iran.The same engineers who built strong encryption into the i Phone to protect our users would, ironically, be ordered to weaken those protections and make our users less safe. Surely someone there could disable a four-digit passcode on a consumer phone?That's because most of the important information on your i Phone is encrypted.But Apple CEO Tim Cook writes that such an exploit would lay out a route for invading many other Apple devices: The government suggests this tool could only be used once, on one phone. Once created, the technique could be used over and over again, on any number of devices.
In the physical world, it would be the equivalent of a master key, capable of opening hundreds of millions of locks — from restaurants and banks to stores and homes. Apple wanted to build a backdoor into encrypted Apple data, the company couldn't.
He wasn't talking specifically about four-digit pass codes, but it's interesting that in this case he believes a backdoor is possible.
The four-digit passcode, along with a key built into the phone's hardware, is necessary to de-crypt the messages and photos on your phone. Apple is better able to access that data than the FBI because it holds a set of keys.
Those keys won't unlock the vault, but they do allow it to access and modify the vault's locking mechanism — and to make changes that would allow the FBI to pick the lock on its own.
Right now, if you enter an incorrect passcode on an i Phone 5c (the model owned by the shooter) you just don't get in.
Make some more mistakes and i OS will make you wait longer and longer between each attempt.