user admin password = "PLAIN:flussonic"

Then disable or delete the default admin user by commenting it out. Restrict Admin UI access to specific IPs or subnets:

http listen 9443;

Scanning bots target port 8080. Change it to a non-standard port (e.g., 9443) in the config:

Flussonic Admin Ui Default Password File

Learn more
flussonic admin ui default password