Apple Thursday released a patch to macOS 11.2 that aims to protect recent Macs from damage when connecting to a non-compliant powered USB-C device. Some users have reported that their Macs have gone blank and become totally unresponsive after connecting them to a USB-C dock or hub.
The issue is apparently with some third-party powered USB-C hubs that are not fully compliant with the USB-C power specs. The 11.2.2. patch is just over 2GB and the notes are brief:
macOS Big Sur 11.2.2 prevents MacBook Pro (2019 or later) and MacBook Air (2020 or later) models from incurring damage when they are connected to certain third-party, non-compliant powered USB-C hubs and docks.
That's all Apple says there is to this update. It's probably a good idea to grab it, but if you don't use powered USB-C devices the urgency is not as great.
How to update macOS Big Sur to 11.2.2
Before updating your Mac, it’s a good idea to back up your data, just in case the update causes problems.
To install the update, you need an internet connection of course. Also, your Mac will need to restart in order to finish the installation. Here are the steps.
Click on the Apple menu.
Select About this Mac.
In the window that appears, go to the Overview tab if it’s not already open.
Click on the Software Update button.
When you are ready to install, click on the Update Now button. The installation takes several minutes, depending on the speed of the internet connection.
You can also update your Mac by opening System Preferences and clicking on Software Update.