Thanks to a bug in the iOS, texting someone "لُلُصّبُلُلصّبُررً ॣ ॣh ॣ ॣ 冗" will cause their phone to crash and reboot immediately.
It's suspected that the glitch is related to the way iPhones and iPads render Arabic characters. When the text pops up as a notification, the mobile device tries to shorten the message with an ellipsis. That's when it runs into trouble: trying to insert an ellipsis in the middle of non-Latin script characters—including Arabic and Chinese letters—causes the whole device to give up and restart.
Luckily, there's only one known series of symbols that can trigger this bug. It's unlikely the phrase will be used accidentally, so the only real threat is a mischievous friend. To combat this, you can turn off notifications until the error has been corrected. Some victims claimed that they could no longer access their text messages as a result. One Redditor suggested sending a photo via the photo app to the friend who sent the dangerous message. This will allow you to reopen messages and delete the text conversation in question.
mental_floss urges you to engage in safe sending, and refrain from forwarding this malicious text to your friends and family.