Apple has released iOS 11.2.6, which includes a bug fix for the Indian language (Telugu) character that crashes an iPhone and makes apps. You can now install iOS 11.2.6 using 3uTools to fix this bug. 

Please back up your iDevice as always before you restore to another iOS version. 

Step 1 Connect your iDevice to PC with USB cable and then launch 3uTools. 

Step 2 After 3uTools successfully connects your iDevice, navigate to "Flash & JB" -> "Easy Flash", there are compatible iOS versions options and please select iOS 11.2.6 firmware. (Select the checkbox "Retain User's Data While Flashing" if you want to reserve data on your device.)

After you click "Flash", there will be a popup, read it deliberately and click "OK" to start flashing.

Step 3 Please do not disconnect your iDevice until the update has finished. It can take a few minutes. Your device will be updated to iOS 11.2.6 and reboot once or twice during the process.