A hacker has identified a combination that can temporarily disable iPhones. It goes without saying that you should not try this yourself.
The combination consists of a white flag emoji, a "0" and a rainbow emoji. Upon receiving the message, the iPhones freeze for around a minute and users are forced to restarted. This has been sent around as a malicious message attack, with the victim powerless to prevent a repeat attack.
It's thought that the hack does not impact those with the most up-to-date version of the iOS, 10.2.
The impact of the message seems to stem from the fact that the rainbow flag emoji is not an official emoji. Apple creates it by combining the code from the white flag and the rainbow emoji. The two are joined by a hidden character known as VS16. The offending message, featuring three characters causes trouble because the VS16 is working, trying to bring the two emoji together, but can't because the "0" is in the way.
The bug was highlighted on "EverythingApplePro", a YouTube account, which often shows off various iPhone pranks.
If you receive this message, don't panic as your phone will snap out of the freeze after a few minutes. That being said, however, do not send it to anyone, even as a joke as there is no way of knowing how each individual phone will react.