iPhone doesn’t even have to connect to the network to mess up.
Back in June, security researcher Carl Schou found that when he joined the network “%p%s%s%s%s%n”, his iPhone permanently disabled its wifi functionality. Luckily, this was fixed by resetting all network settings, which erased the villainous wifi name from his phone’s memory. You would think that would have been the end of connecting to networks with weird and fishy sounding names, but you are not Schou.
On Sunday, he decided to try his luck again by investigating a public wifi network named “%secretclub%power”. According to Schou, just having an iOS device in the vicinity of a wifi network with this name can permanently disable its wifi functionality.
“You can permanently disable any iOS device’s WiFI by hosting a public WiFi named %secretclub%power,” he wrote on Twitter. “Resetting network settings is not guaranteed to restore functionality.”
Schou apparently struggled to find his way out of this one and get his wifi functionality back. He said he reset network settings multiple times, forced restarted his iPhone, and even contacted Apple’s device security team. The researcher eventually got some help from Twitter, which advised him to manually edit an iPhone backup to remove malicious entries from the known networks plist files.