Apple have released iOS 12.4.1 to all iPhones, iPads, and iPods running iOS 12. This is following the accidental undoing of a major security patch that was introduced in iOS 12.3 which fixed a vulnerability in iPhones, iPads, and iPods. This vulnerability enabled jailbreaks and other exploits to be created and run on iOS devices.
The iOS 12.4.1 update is available on all iPhones, iPads, and iPod touches running any previous version of iOS 12. You can download the update via OTA (over-the-air) by navigating to Settings > General > Software Update. You can also connect your iOS device to iTunes and update through iTunes. You need a computer for that method. iOS 12.4 is available to download now!