A rather intriguing phenomenon has been circulating reddit and it has to do with a recently discovered vulnerability affecting most current iPhones. It appears that if you set the date on a 64-bit iOS device to January 1 1970 and then restart it, you get a vicious boot loop. Worse yet, simply restoring the unit through DFU can’t fix the issues and you will most likely end up on a trip to the nearest Apple Store.
Digging a bit deeper into the problem, it seems it relates to UNIX time, which is basically a standardized counter for the number of seconds since January 1 1970. It plays a pretty important role in the tech realm and from what we can gather, rewinding the clock so far back on the affected Apple devices, plus any potential timezone offset or other transformation to obtain a date and time metric results in a corrupt result that prevents the OS from booting. The bug was allegedly discovered by chance, as it so happens that iOS allows you to go as far back as 1970 withing the date setting, but doing so requires a lot of scrolling.
As for the affected devices, it seems the odd behavior is only exhibited by 64-bit versions of iOS, which would go as far back as the A7 chip and iOS 7. In model terms that should mean any iPhone 5s an newer models, as well as potentially iPad Air and iPad Mini 2 tablets, running on at least iOS 7. Besides being a curiosity that we definitely urge you not to try on your device, unless you really feel like sending it in for repair, the bug actually has quite a lot of damage potential if it falls into the wrong hands.
Consider this, most current devices, including the affected Apple tech, rely on NTP servers to automatically set their time and date. If a hacker were to theoretically spoof responses and pose as such a server on a Wi-Fi network, he could potentially kill every current iPhone or iPad on the same network.
That does sound scary, but fear not, as there is a fix. It is a hardware one, but simply entails disconnecting the battery, waiting a bit and connecting it back up, which resets the corrupt settings. Sadly, that usually requires an Apple technician, unless you want to open the unit up yourself and void your warranty. Depleting the battery fully has also worked for some users, but it takes time and effort.
Apple has been notified about the issue and all that remains is to see when and how it gets addressed. In the mean time, again, please resist the urge to try it for yourself, now that you know what is going to happen.