>No, but you stop that by refusing to let the printer talk out of your network at all. That's a lost battle, honestly. If you block traffic from the printer to

>No, but you stop that by refusing to let the printer talk out of your network at all. That's a lost battle, honestly. If you block traffic from the printer to the internet, it starts sending UDP with faked source addresses. If you deploy a VLAN the printer can fake the VLAN Tags. If you physically seperate the printer from any direct connection to your firewall, the printer can look for anything on the network it can use to bounce traffic from (like a DNS server or a computer accepting ICMP echo requests) A sufficiently dedicated attacker can and will extract information through covert channels.