> That is, the attacker either needs to have been allowed to connect to your WiFi (either through another vulnerability or voluntarily) or attached a cable to y

> That is, the attacker either needs to have been allowed to connect to your WiFi (either through another vulnerability or voluntarily) or attached a cable to your WiFi router or your cable modem. no you just have to visit a malicious link, through dns rebinding any local attack against a router can be done remotely.