iPhone text 'bomb' can crash iOS 13 with just a string of letters

A Sindhi character and the Italian flag emoji can break phones, iPads, Macs and Apple Watches

(AFP via Getty Images)

A new Apple text "bomb" forces iPhones that receive it to crash.

The innocent-looking message – which is made up of the Italian flag emoji and a Sindhi character – overloads the device and forces it to shut down.

It works on Macs, Apple Watches and iPads as well as iPhones and there is hardly anything that can be done to stop the damage.

The bug seems to exploit a problem in the message notifications on the phone, which means that it is unable to display the notification about the new message and crashes the app.

While the problem will sometimes simply force the Messages app to crash and re-open, some users have reported that the problem can also force the iPhone itself to shut down. And it is not limited to the Messages app within the phone, with any notification – such as a WhatsApp or Facebook Messenger notification – potentially being used to exploit the issue.

It is far from the first such bug to hit the iPhone. In 2015, the phone was famously hit by a bug called "Effective Power" and in 2018 another example was named "ChaiOS" – both bugs used different words and characters, but were otherwise nearly identical to the latest bug.

Initial reports had suggested that the bug required the Sindhi characters in addition to an Italian flag, and that still seems to be the most popular version of the message. But some have claimed that other emoji will work too, with videos showing iPhones reduced to almost not working at all after receiving the text with a variety of different characters.

While the bug mostly forces the phone to crash and reload itself, some users have reported that it can cause much more extreme problems such as stopping the display working and that the issue can only be resolved if the device is placed into "DFU" or recovery mode, which involves resetting it entirely.

There is no easy way to protect against the bug. It appears to affect notifications about messages rather than the messages themselves, meaning that turning off notifications could stop any possible attacks, but that would obviously also mean not receiving notifications about any other non-problematic messages.

The only way to avoid the problem entirely is for Apple's software to be updated to allow it to handle the message. In the past, Apple has rolled out such updates a few days after the bug appeared.

The bug does not seem to allow hackers any access to the phone, or compromise it in any lasting way. As such, it is more frustrating than it is dangerous.

Apple is yet to comment on the problem.