A new bug has been found, which allows anyone to crash an iPhone with a three-character text message.

First revealed in a YouTube video from EverythingApplePro, the issue affects iPhone models running older builds of the iOS operating system. The easiest way to protect yourself, therefore, is by updating to the latest version of iOS.

The message itself comprises a white flag emoji, a ‘0’ and a rainbow emoji, exploiting a workaround iOS uses in order to create the rainbow flag emoji, which isn’t an official emoji.

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Ordinarily, iOS would create the rainbow flag by linking the white flag emoji with the rainbow emoji, using a hidden character known as VS16. However, in this case the two emoji are separated by the ‘0’, causing the system to crash and rendering the touchscreen and physical buttons unusable.

Fortunately, the effect is only temporary, and affected phones should continue to operate as normal after a minute or so of inactivity.

If you’re unable to update to the latest version of iOS due to storage requirements and a prankster takes aim at you by sending the message multiple times, you can block their number.

A separate bug designed to crash the messages app whenever it launches is also being reported by users. This one is triggered by a large contact file sent from the iCloud Drive app.

As the description attached to the EverythingApplePro video notes, clicking this link on your iPhone should create a new message and, in doing so, neutralise the messages app bug.