https://arstechnica.com/gadgets/2021/06/connecting-to-malicious-wi-fi-networks-can-mess-with-your-iphone/

There’s a bug in iOS that disables Wi-Fi connectivity when devices join a network that uses a booby-trapped name, a researcher disclosed over the weekend.

By connecting to a Wi-Fi network that uses the SSID “%p%s%s%s%s%n” (quotation marks not included), iPhones and iPads lose the ability to join that network or any other networks going forward, reverse engineer Carl Schou reported on Twitter.