A newly discovered iOS exploit shows how just wary you should be of mystery Wi-Fi connections – this latest one, in particular, will fully disable your WiFi functionality if joined.
That’s right – a rather strange vulnerability has been discovered that affects both iPhone and iPad users. Carl Schou on Twitter revealed that after joining a local Wi-Fi network with the unusual name “%p%s%s%s%s%n” his iPhone permanently switched off its Wi-Fi functionality, meaning other networks could no longer be joined – even after a device reboot.
With this bug in action, toggling the Wi-Fi switch in Settings no longer works, with iOS immediately toggling it off again. That means no more internet access (except via cellular connections like 4G) and no more AirDrop. Uh oh.
Though it may seem unlikely you’d find and connect to a Wi-Fi network with this name, now the exploit is known you can expect bad actors and cruel pranksters to change their personal hotspots and public Wi-Fi connections to this name in order to mess with other people’s devices.
If you’re in the habit of using free public Wi-Fi, think twice before joining – it’s possible there are other text strings that cause similar bugs, so watch out for any network with a suspicious name and lots of “%” symbols. The way these characters are read in code means there’s potential for this sort of thing to confuse iOS, which is seemingly how this particular bug works.
Though the prospect of permanently broken Wi-Fi is scary, luckily there is a fix if something like this ever happens to you. You can reset all connectivity details back to factory settings, which will wipe the bug – but it also means you’ll need to teach your device your Wi-Fi passwords again from scratch as if it was a new device. If you have to do this, open Settings and head to General > Reset > Reset Network Settings.
Before long, we’d expect Apple to release a fix for this bug, but it’s useful to know that this kind of thing is possible in case more vulnerabilities like it are discovered and exploited.