Four characters is all it takes to crash iOS, iPadOS devices

Typing a special four-character string will crash your iPhone thanks to a newly discovered, albeit benign, bug in iOS and iPadOS. 

The bug affects SpringBoard, the underlying application that manages iPhone and iPad home screens. Simply typing “”:: in a select few search bars within iOS and iPadOS will cause apps to abort in different ways.

Typing the string into the search bar within the Settings and Notes apps, for example, will cause them to fall over, returning the user to the home screen.

Doing the same in the search field of the App Library, accessible by swiping to the far right of the home screen, causes iOS to enter a soft crash. The screen goes black displaying only a small spinning progress wheel, before returning the user to the lock screen.

El Reg tested the above conditions, and all led to the crashes as described. We also tested the same method across all of Apple’s native apps and search fields we could locate, but no others resulted in a failure of any kind.

The same crashes can also be achieved with “”: and any additional fourth character. This includes pasting anything after the first colon. Another, slightly lengthier way to trigger it is to insert any character between the quotation marks and any character after the first colon.

Security researcher Patrick Wardle took a look at an iOS crash report to see what exactly was happening under the hood. However, he told TechCrunch, which first reported the bug, that it wasn’t malicious in nature and couldn’t be harnessed for any kind of attack.

It’s certainly not as nasty as text-based bugs of yesteryear, like the one from 2018 that allowed anyone with your phone number to issue a text bomb that didn’t even need to be opened to cause a device to freeze.

Some dubbed this at the time as the second incarnation of Effective Power – the name given to a similar dastardly text bug from 2015 that forced recipients’ devices to reboot.

This in turn followed another similar bug in 2013, this time a five-character text-based bug that took apps down. Facebook even banned the string from being posted because of how frequently its users were causing apps to crash.

El Reg asked Apple to comment, but it didn’t immediately respond. ®