What are TCP FIN scans?

Answer 1

TCP FIN scans are a type of network scanning technique used to determine the status of ports on a target system. By sending TCP packets with the FIN (finish) flag set, the scanner can check for responses that indicate whether a port is open, closed, or filtered. If the port is closed, the target typically responds with a RST (reset) packet, while open ports may ignore the FIN packet, making this technique useful for stealthy reconnaissance. This method can help evade detection by firewalls and intrusion detection systems, as it does not conform to standard connection initiation requests.