So I got alt tabbed out of a game I was playing and when I looked in the notifications of Bitdefender I saw that something was allowed through the firewall. I denied it so I don't have the exact file path but I think it was like
c:/Windows/Temp/Rarsfx1/packages/installer.exe
I had this same file like a year ago, and again I've looked up things and there's really nothing conclusive. The folder and file deleted itself too when I right clicked on something called "installation file" or something similar that was in my task manager. Same thing that happened when I first saw Rarsfx a year ago.
Only post I've found that said anything was this, an old Bitdefender forum post.