Can unauthosed entry be gained through a running copy of Deluge

Running Mate 19.10 at the moment. I've used Deluge for many years with the Firewall always turned on but Deluge 00h00-18h00/7 days a week on TorrentDay mainly.
For years I experienced no problems. During 2018/9, the 'space used' using Clonezilla, during some weekends showed an unexplained increase which I countered on Mondays by reloading an image from the previous week
I've cut back the days run from Tuesday to Thursday 05h00-16h00 to prevent apparent intrusions but I'd like to run 00h00-18h00/7-7.
Is Deluge vulnerable, is the built in firewall the best or a compromise?