64-bit iPhones and iPads get stuck in a loop when set to January 1, 1970

Take a 64-bit iOS device—iPhone 5S or newer, iPad Air or newer, iPad Mini 2 or newer, sixth generation iPod touch or newer—laboriously set its date to January 1, 1970, and reboot. Congratulations: you now have a shiny piece of high-tech hardware that's stuck at the boot screen, showing nothing more than the Apple logo... forever.

Posted on Reddit and subsequently demonstrated on YouTube, it appears that iOS has a rather embarrassing software flaw. Redditors testing the bug have found themselves with unusable phones, and there are reports that vandals have been resetting the clocks of display devices in Apple stores.

So far, taking advantage of this bug requires a few minutes of physical access, as it takes a while to wind the date back 46 years in the settings app. There is concern that Wi-Fi devices could be vulnerable to malicious data from NTP (network time protocol) servers. NTP is used by many operating systems to set the time and date of a device, and its data is both unencrypted and unauthenticated, making spoofing relatively straightforward. NTP clients should not generally change the time and date by such large amounts, so this may not be an issue, but iOS's behavior in this regard is currently unknown.