During host discovery, what does Nmap send to port 80?

Prepare for the Penetration Testing and Vulnerability Analysis Test with a range of challenging questions. Study with multiple choice format, hints, and detailed explanations to ace your next exam!

Multiple Choice

During host discovery, what does Nmap send to port 80?

Explanation:
Host discovery uses lightweight probes to check if a host is reachable without opening a full connection. Nmap uses a TCP ACK probe to port 80 for this purpose. Sending an ACK without completing a handshake is less intrusive and helps determine reachability behind basic firewall rules. If the host is up and port 80 isn’t filtered, you’ll typically get a RST response, signaling the host is reachable even though the port is closed. If there’s filtering, there may be no response, which still indicates the host is up but protected. Using a SYN probe would start a full handshake and be more intrusive, while FIN or RST probes don’t reliably indicate reachability in this context. So, the TCP ACK probe to port 80 best serves host discovery.

Host discovery uses lightweight probes to check if a host is reachable without opening a full connection. Nmap uses a TCP ACK probe to port 80 for this purpose. Sending an ACK without completing a handshake is less intrusive and helps determine reachability behind basic firewall rules. If the host is up and port 80 isn’t filtered, you’ll typically get a RST response, signaling the host is reachable even though the port is closed. If there’s filtering, there may be no response, which still indicates the host is up but protected. Using a SYN probe would start a full handshake and be more intrusive, while FIN or RST probes don’t reliably indicate reachability in this context. So, the TCP ACK probe to port 80 best serves host discovery.

Subscribe

Get the latest from Passetra

You can unsubscribe at any time. Read our privacy policy