A security feature has been discovered in iOS 18.1. This feature forces the iPhone to automatically reboot when it is not active for a long time. In such a situation, it is becoming difficult for both thieves and police to access locked devices.

An investigation by 404 Media states that this feature called inactivity reboot automatically restarts those Apple iPhones which remain locked for about four days. In such a situation, when this iPhone reboots, it enters the highly secure 'Before First Unlock' (BFU) state. This requires the original passcode to access it.

Law enforcement officials first noticed this problem when iPhones stored for forensic examination were mysteriously rebooting themselves. Christopher Vance, a forensic expert at Magnet Forensics, has already advised police officers to prioritize collecting evidence from iOS 18 devices when they are in the 'After First Unlock' (AFU) state, before they automatically reboot.

Dr.-Ing. Jiska Klassen, research group leader at the Hasso Plattner Institute, confirmed that this is not a bug, but a security feature deliberately implemented by Apple in iOS 18.1. According to a report by 404 Media, the existence of this feature was confirmed through code analysis.

Matthew Green, a cryptographer and associate professor at Johns Hopkins University, said that this feature also affects the functioning of government officials, but its primary target is criminals. Green told 404 Media, 'Remember that the real threat here is not the police. It is people who steal your iPhone for malicious purposes.' He said that this feature prevents thieves from developing technology to crack stolen phones by keeping them active for months.

Chris Wade, founder of mobile analysis company Corellium, explained that when the iPhone is in a locked state, a timer is activated, which automatically reboots after four days. In such a situation, it forces investigators or potential thieves to start their efforts to access the device from the beginning.

This feature represents Apple's new efforts to increase the security of the iPhone. However, it has created new challenges for law enforcement agencies conducting forensic investigations on seized devices.