Nessus UDP Scanner
Info Nessus Plugin ID 34277
SynopsisIt is possible to determine which UDP ports are open.
DescriptionThis plugin runs a UDP port scan against the target. It is possible to determine which UDP ports are open by sending UDP packets on every port. If the port is open, the application will most often keep quiet.
If the port is closed, the TCP/IP stack may send back an ICMP Host unreachable / bad port packet. If the target machine is protected by a firewall, this technique cannot distinguish open ports from filtered ports and fails. As the ICMP rate is often limited, this scan is slow.
SolutionProtect your target with an IP filter or implement ICMP rate limitation.