iOS 12.1.4 exists many errors: caused SIM card recognition failure, loss of WiFi connection
Last Friday, Apple released iOS 12.1.4 that designed to fix serious security vulnerabilities. In addition to fixing security vulnerabilities in FaceTime group calls, it also fixed a “memory crash” and a malicious code to get kernel priority, as well as live photo vulnerabilities. However, according to many upgraded users, upgrading the 12.1.4 version caused SIM card recognition failure, loss of WiFi connection and other network connection problems.
@AppleSupport I updated iPhone 7 Plus yesterday with update 12.1.4. Cellular date virtually none existent! .06-.10 speed. Did all the workarounds could find. Even reset phone. No change. Help!
— Keith (@1goldengator) February 10, 2019
Forbes also reported many other user reactions, including the 12.1.4 upgraded iPhone device AirPods, Touch ID and voice memo, and the degradation of cellular signals. These users have never experienced similar problems before upgrading.
https://twitter.com/JamesGronroos/status/1094450198233763840