Apple on Monday released iOS 12.4.1, an update to the operating system for the iPhone, iPad, and iPod touch. The notes with the update don’t say much, only that the update “provides important security and stability updates.”
You can find more detail about the update in an Apple support document. The update patches a vulnerability that allowed jailbreaking of an iOS device. This vulnerability was actually patched in an older version of iOS 12, but it was reopened recently.
How to install iOS 12.4.1
Before installing the update, it’s a good idea to back up your device.
In your iOS device, launch the Settings app.
Tap Software Update.
Your device will check for the availability of the update. If it’s available, you’ll see a screen describing the iOS 12.4.1 update. Tap Dowload and Install when you are ready to proceed.
You will need to enter your passcode. After that the download and installation will take several minutes.