Researcher demonstrates Apple iOS 18 security feature rebooting an iPhone after 72 hours of inactivity

midian182

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In brief: Apple has a history of frustrating law enforcement, from denying requests to help unlock phones to refusing to add backdoors to its software. The latest Cupertino feature annoying officers and forensic experts is iOS 18's inactivity reboot tool, which reboots an iPhone after three days of inactivity. Now, researchers have demonstrated it in action.

Last week brought reports of police officials warning other departments that iPhones being stored in evidence for forensic examination were rebooting themselves. 404Media writes that security experts later confirmed that Apple had quietly introduced the feature in iOS 18.1.

Rebooting an iPhone makes it more difficult to break into using forensic tools such as Magnet Forensics' Graykey. The company wrote its own post on the feature and its security implications.

Jiska Classen, a researcher at the Hasso Plattner Institute and one of the first to notice the rebooting, published a video demonstrating it (via TechCrunch). The video confirms that iOS 18 reboots a handset after 72 hours of inactivity. The iPhone does this without any prompts or warnings.

The problem being faced by those trying to break into iPhones – both criminals and authorities – is that the device is in its most secure state after a restart. It is in this Before First Unlock (BFU) state that the user's data is fully encrypted and almost impossible to access.

Apple's handsets indicate that passcodes are required after a restart, while iPhones in After First Unlock (AFU) states can be unlocked using just Face or Touch ID. Some data is unencrypted and easier to extract with certain tools in the AFU state.

Apple added a 7-day inactivity reboot feature in iOS 18, shortening the length of time to just three days in iOS 18.1.

Magnet Graykey suggests the simple solution is to ensure law enforcement extracts evidence from iPhones using its tools as quickly as possible – I.e., within 72 hours of seizing a handset.

This isn't the first time Apple has annoyed law enforcement. The Cupertino company famously refused to help the FBI access Syed Rizwan Farook's locked iPhone, one of the San Bernardino shooters.

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The problem being faced by those trying to break into iPhones – both criminals and authorities – is that the device is in its most secure state after a restart. It is in this Before First Unlock (BFU) state that the user's data is fully encrypted and almost impossible to access.
No, it hardens the encryption keys. Your iPhone data is always "fully" encrypted. (Otherwise, they could just copy it over and read it.)

Embarrassingly, the author would know this if he'd read the X thread he linked in the article:

"Inactivity reboot puts your iPhone into "Before First Unlock" state, effectively locking encryption keys in the Secure Enclave Processor. Even if thieves leave your iPhone powered on for a long time, they won't be able to unlock it with cheaper, outdated forensic tooling. (2/4)" - Jiska @naehrdine
 
Most agency's who are supposed to capture data off of a device, usually let or put the device for a longer period of time until a proper working exploit or kit is available.

With this reboot, it makes the phone stronger, which is a good thing.
 
Incativity ?????
So if I don't play with my cat for 72 hours my iphone will reboot?
Yes. Apple has joined forces with the ASPCA to ensure all cat owners are invested in the happiness of their feline friends. It may also shorten the time for when cats will overpower humans (this is a foregone conclusion) and takeover society, as we all know who is in charge.
 
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