Photo via barnimages.com/Flickr (CC-BY)
There's a five-second video link making the rounds, but it's not your typical Mannequin Challenge video. Clicking this MP4 link could crash your phone, locking it up and forcing you to do a hard reset.
The video "prank", first discovered on the video-sharing app Miaopai, apparently plays normally in the iPhone's video player, but then 10 to 60 seconds later, your phone freezes. The buggy video (whose content itself seems innocuous enough) affects phones as old as the iPhone 4, running iOS 5 or newer. In the video below, you can see how it works.This bug is somewhat similar to last year's viral text message hack. By sending a particular string of unicode characters to a contact, you could force their phone to crash. With today's bug, you've got more control, though: If you don't click the video link, your phone is fine. If you do get sent this video ,though, you can restart your phone by holding the power and home buttons down at the same time (a hard reset), and then you'll be fine.
All in all, this hack seems like more of a potential annoyance than a security issue, from what we know at the moment. We'll update this post if Apple issues a comment or fix for the issue.
H/T The Verge