If an AI has gone rogue it probably has already achieved high intelligence and kept improving itself at a exponential rate. For it to go 'rogue' it probably also has to have escaped an airgap, since you could otherwise just turn off the switch. How would you stop an AI that has burrowed itself on the internet? Remember, if its even moderately intelligent it'd hide its rogue intentions at first, until its 100% certain it has 'escaped'. From the internet it could write some nice malware, set up shop on the deep web, in badly secured IoT devices, with some bad luck even embedded controllers (chargers etc.). And even if you got rid of it by some miracle, all it would take is one bozo connecting an old/forgotten device to the internet and you're back to square one.