An issue with Apple's latest iOS software allows users to send a specific string of characters via text to shut down an iPhone remotely. The message also affects the Apple Watch, if associated with the same device to which the code was sent.
The message was revealed on Reddit late Tuesday by user cbhunt14.
After gaining some media attention, the public has now turned the system glitch into a prank to turn off their friends' devices.
And social media users are not happy about it...
"We are aware of an iMessage issue caused by a specific series of unicode characters and we will make a fix available in a software update," Apple said in a statement to CNBC.
In the meantime, if you want to protect your iPhone from getting the message, you can try doing this:
CNBC's Josh Lipton contributed to this story.