Here’s how it works – if you attempt to connect to a wireless networks with a percent sign (%) in it, Apple has trouble interpreting the name and the wireless networking stack in the device crashes. Security researchers were able to successfully reproduce the problem by creating a wireless SSID “%p%s%s%s%s%n” and brick the wireless capability of iOS devices.
If you do end up damaging your wireless stack, rebooting won’t fix it. Your iPhone’s WiFi can be restored by resetting network settings (Settings > General > Reset > Reset Network Settings).
It’s a painful action to take, given that it will wipe out all of a device’s Wi-Fi passwords, but it’s a lot better than the prospect of an iPhone’s Wi-Fi having been “permanently” barbecued.
Stay safe out there,
Please note: We will be closed on Monday, July 5th in observance of Independence Day.