I take it that this was after Running the so called Smart Scan - to my mind this is a promotion of Avast paid products. Whilst there is a perceived security weakness in the notification.
I have got by without any of these i all of my time using computers from way back to Amstrad PCW in the mid 1980s. Then I bought a very early PC with Win 3, My last 4 years in the Army as a computer systems analyst programmer.
Then a new PC Win 95, then Win 98, skipped win 2000, win XP, a very short stint on Win 7 (second 10" notebook computer) and then Win10 my current, hold out version.
I have been using Avast Free for over 21 years now and never felt the requirement