what exactly do you mean? I tought piHole sits "between" the tv and your modem? I mean it probably can easily firewall those ips.
Edit: nvm PiHole is only a dns thingy.
So if say your TV calls out to backdoor.example.com - then PiHole can block it.
If instead it calls out to 1.2.3.4 (i.e no DNS lookup) - then PiHole won't block it for you, you'd have to instead set up controls on the firewall/router/etc to filter traffic.
Wanted: Firewall blocking all traffic directed at IP addresses not obtained from OS DNS resolver.
aka dynamic application level FQDN Egress Filtering. Mayor Cloud providers (aws, azure) and bigger firewalls (fortinet, cisco, paloalto) already offer ~half of what I want.
I want a little deamon that listens for DNS queries/replies and modifies firewall rules accordingly.
So, it could still bypass piHole and still resolve hostnames.
At the router level, I then forced all 8.8.8.8 traffic to be transformed into traffic to my pihole.
You can do the next step, but you need a router that supports it and the patience to handle it.
You shouldn’t need to do this.
So, if it is using HTTPS for DNS resolution, I don’t know how you would block that.
If you could install a self-signed cert onto the device, you could MitM the HTTPS traffic and see what it is doing.
By filtering traffic sent from that particular device based on a query to your DNS filter to approve or deny the destination address. (Some implementation work probably required.)