Now Samsung Galaxy S10, Galaxy Note 20, Galaxy S20 FE and Galaxy Note 10 Lite has joined the list. Most of the security vulnerabilities have been addressed. It also brings some bug fixes which were available in the previous build. Thus, you should download and install the update to your Samsung Galaxy which will come as an OTA update to your phone. You can manually check for the update from Settings > Software update >Download updates manually. If there is no update showing on your device, then wait for few days for the update to come to your device as it is being released phase-wise manner or you can manually flash the full firmware using Odin Flash Tool.
Changelog
December 2020 Google Security patch Bug Fixes Security and Performance improvements
Steps to Install security update on a Galaxy phone
Disclaimer
Installation Guide (Manual Flashing using Odin)
If the installation is successful, you will see the message Pass in the Log Tab. Or Using Frija Samsung Firmware Download Tool
Odin Flash Tool
Check sammobile website to get the latest firmware for your device Via SamMobile
