A bug in Apple’s iOS means that anyone can crash an iPhone by simply sending it a certain string of characters in a message.

It was reported by Action Fraud UK that users on Redditt have found that iPhones can be crashed if they receive a text message containing one specific line of Arabic characters and symbols.

This causes the iPhone to instantly crash, reboot and then power off, leaving the Messages app unusable once the iPhone turns back on. According to reports it can also crash Apple Watch, iPad and Mac too.

Currently there is no way to keep phones from falling victim, although Apple has said:  “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”.

Those worried about being attacked can protect their iPhone from the bug by turning off notifications for text messages, or hiding the previews that show up in banner notifications.