TL; DR
- According to a researcher, a newly discovered iOS bug can disable an iPhone’s Wi-Fi connectivity.
- Connecting to a specific Wi-Fi network with “%” symbols appears to be causing the problem.
- The only known workaround is to reset the device’s saved network settings.
If you own an iPhone and don’t want to crash your device’s Wi-Fi functionality, it’s a good idea to check the name of a network before joining it. A security researcher has apparently discovered an iOS bug that can disable the Wi-Fi capabilities of an iPhone.
Carl Schou, the researcher in question, found that an iPhone’s Wi-Fi connectivity remains “permanently disabled” when connected to a network called “% p% s% s% s% s% n”. According to BleepingComputer, Schou tested this theory on an iPhone XS with iOS 14.4.2. In particular, the publication, other researchers and users on his Twitter thread have confirmed his findings. In particular, Android does not appear to be affected by this problem.
After I joined my personal WLAN with the SSID “% p% s% s% s% s% n”, my iPhone permanently deactivated the WLAN functionality. Neither rebooting nor changing the SSID fixes this: ~) pic.twitter.com/2eue90JFu3
– Carl Schou (@vm_call) June 18, 2021
Schou notes that restarting the device will not fix the problem. Changing the name of the WiFi network does not solve the problem either. A connection to another network is also not possible as this error apparently destroys the page with the WiFi settings.
So what’s causing the problem? It is believed that an error in the format string is causing the problem. iOS apparently interprets the letters after the “%” as commands or variables and not as the actual WiFi SSID.
How to Fix iPhone WiFi Error
As easy as it is to get into this mess, there is an equally easy way out. On the way to the settings > General > Reset to default > Reset network settings on your iPhone will delete the Wi-Fi name from the device’s logs. However, you will need to re-enter all secure Wi-Fi networks and other network information.
While it is a temporary nuisance, the bug does not appear to be a security flaw and is unlikely to be exploitable by malicious actors. That said, it would be a cruel ploy to play on iOS users who are no smarter.
