Bricking the iPhone requires sending someone a malicious vcf file through iMessage and as soon as the receiver opens that file, it will disable the Messages app on their iPhone and it will stop working. There is also a solution for this bug. It will require opening the following website on the iPhone which is affected and it will open the Messages application and then it will be fixed automatically.
This file is also effective on some Android devices and it even crashes the Contacts app in Windows 10 devices. So, it looks like that the malicious file takes advantage of operating systems. This bug is now viral on social media and soon Apple will be fixing it in next update.
If you want to try this prank then watch the video below as it has all the information about this bug.