Ports Open/Close
With BOLD is the attacker/client send flags
open: SYN, SYN/ACK, ACK, RST
close: SYN, RST
open: SYN, SYN/ACK, RST
close: SYN, RST
open: FIN/URG/PSH/NULL, No Response
close: FIN/URG/PSH/NULL, RST/ACK
open: FIN+URG+PSH, No Response
close: FIN+URG+PSH, RST/ACK
open: No Response
close: RST
Attacker/client sends only ACK package. If he receives on RST flag that means the port is there and open. Also on "NO RESPONSE" means that a stateful firewall is present. On a RST flag means no firewall is in place.
open: No Response
close: ICMP port unreadable UDP port scanning is often unreliable, as firewalls and routers may drop ICMP packets. This can lead to false positives in your scan, and you will regularly see UDP port scans showing all UDP ports open on a scanned machine. People often forget to scan for UDP services, and stick only to TCP scanning, thereby seeing only half of the equation.
open: No Response
close: RST
open: RST
close: No Response
Last modified 3yr ago