All Ports listed as open using NMAP with 'discovery' and 'don't ping' selected. What does this mean?
Posted on 2005-05-14
I am trying to make sure my 2600 router is secure so I am doing port scans from a remote network. On my router, I have all ICMP traffic blocked and am only allowing VPN traffic in unless it is established outbound traffic. I performed a 'SYN Stealth scan' and since ICMP is turned off, the router could not be found. However when I went to 'discovery' and used the 'don't ping' option, every port showed open. I tried scanning a bunch of other IP addresses from other companies and they showed the same with these options selected. Is my network at risk?