If you mean something like HTTP server logs, then clients should be rotating their addresses regularly, and router firewalls should be blocking any incoming une

If you mean something like HTTP server logs, then clients should be rotating their addresses regularly, and router firewalls should be blocking any incoming unestablished connections, so you can't just look at a log to find vulnerable computers to talk to. You'd be much more likely to find a vulnerable computer that you can actually talk to by looking at AAAA records for websites. Or if you were a malicious website, wait for people to talk to you, and then send evil responses.