I previously purchased/configured a new Raspberry Pi 4 to run Ubuntu 20.04.1 and Apache. I'm forwarding Port 80 on my AT&T modem to the Raspberry Pi and hosting a few websites with no problems.
I received a new Raspberry Pi today and booted up a new instance of Ubuntu 20.04.1 for the first time. Ubuntu got to the login screen, and while I was getting things set up on my laptop to log in via SSH, my Raspberry Pi suddenly had a chunk of output on the terminal.
I recognize it as something corresponding to public keys, since I plan on adding my own public key for SSH logins. That seemed a bit suspicious to me, as I don't recollect that happening when I set up the original Raspberry Pi. I removed port forwarding from my modem while I wiped the SD card clean and booted up Ubuntu anew, only for the same issue to arise. Is my Raspberry Pi being hacked? Is some external entity adding their own SSH key to Ubuntu before I can log in for the very first time?