J. Glenn Künzler, Sonny Dickson blog:

Earlier this week, news broke of a strange networking issue that can permanently disable all WiFi activity on iOS devices. It’s currently known to affect iOS 14 only, and can cause quite a mess. The news was originally revealed by reverse engineer Carl Schou (via BleepingComputer (story sourced via MacTrast), and while there was originally very little information revealed about the issue or how it functions, we decided to put our research hats on and see what we could discover.

This all started with this tweet:

After joining my personal WiFi with the SSID “%p%s%s%s%s%n”, my iPhone permanently disabled it’s WiFi functionality. Neither rebooting nor changing SSID fixes it :~) pic.twitter.com/2eue90JFu3

— Carl Schou (@vm_call) June 18, 2021

Don’t try this at home. But a fascinating bug.

If you find this interesting, follow the headline link to watch J. Glenn Künzler try his hand to work through what’s going on.