How to fix the “tcpwrapped” error with NMAP scan?
I ran a scan with:
But I am encountering some “tcpwrapped” errors with the following result:
Scan methodology was I'm sure that this is a firewall's or load balancer's game. I tried many ways, such as change source port, source IP, fragmentation, etc.. Do you have any idea/suggestion to bypass the “tcpwrapped” error? On another hand, do you know how to do that in a firewall policy (on any firewall)?
"tcpwrapped" refers to tcpwrapper, a host-based network access control program on Unix and Linux. When Nmap labels something tcpwrapped, it means that the behavior of the port is consistent with one that is protected by tcpwrapper. Specifically, it means that a full TCP handshake was completed, but the remote host closed the connection without receiving any data. It is essential to note that tcpwrapper protects programs, not ports. This means that a valid (not false-positive) tcpwrapped response indicates a real network service is available, but you are not on the list of hosts allowed to talk with it. When this large number of ports are shown as tcpwrapped, it is unlikely that they represent real services, so the behavior probably means something else. You must probably be seeing is a network security device like a firewall or IPS. Many of these are configured to respond to TCP portscans, even for IP addresses that are not assigned to them. This behavior can slow down a port scan and cloud the results with false positives.