Sure, you can impersonate someone (or even anyone). A botnet can impersonate everyone, and make robocalls to everyone. If you're doing a targeted attack, you m

Sure, you can impersonate someone (or even anyone). A botnet can impersonate everyone, and make robocalls to everyone. If you're doing a targeted attack, you might need a significant chance of success - if you can target 10 000 users, you might get away with a 1% success rate, and still make a significant amount (say 60 times 1 000 USD in "emergency" funds).