Apple seems to have introduced an “activity timer” into iOS 18.1 that reboots devices after a set period of time, making it harder to break into them.
We seem to have quickly gotten an answer to the mystery of why iPhones in the custody of law enforcement have been rebooting themselves, making it harder for cops to break them open. Security researchers have found that the latest version of iOS, version 18.1, includes a feature called “inactivity reboot” that restarts a device after approximately four days being in a locked state.
404 Media reported earlier that week that police officers in Detroit were freaking out because iPhones in their custody for examination were randomly rebooting, making it more difficult to crack them open and exfiltrate data that could be useful in investigations. Law enforcement and forensic experts quickly made their way into group chats in order to warn others to get data off devices in their custody as quickly as possible before the reboot happens.
It may seem like a minor issue, but iPhones live in two different states: AFU, or After First Unlock, and BFU, or Before First Unlock. AFU is when somebody has unlocked a device at least once since it was powered on, and experts say devices in this state are generally easier to unlock using exploits.
