NMAP Guide


  1. Basic scan to see what ports have a valid service running on them:

    nmap {host} nmap -v {host}

Pass the -v flag to print a little more information.

  1. Basic scan to just see what ports are open/closed/filtered, but will not actually test the port for a service running:

    nmap --top-ports {number of ports} {host}

  2. Scanning a range of IP addresses or a subnet:

    nmap {host} 192.168.1.2 192.168.1.3 nmap {host},2,3 # multiple nmap {host}-20 # range

    nmap 192.168.1.* # range nmap 192.168.1.0/24 # subnet

  3. Scanning and reading from a list of hosts

    input.txt

    host1.com host2.com {host}

    nmap -iL input.txt

  4. Exclusions:

    nmap 192.168.1.0/24 --exclude 192.168.1.5 nmap 192.168.1.0/24 --exclude 192.168.1.5,192.168.1.254

OR exclude list from a file called exclude.txt

nmap -iL /tmp/scanlist.txt --excludefile exclude.txt
  1. OS Detection of services:

    nmap -A -v {host}

  2. Firewall protection of the host:

    nmap -sA -v {host}

  3. Scanning a host protected by a firewall (very useful):

    nmap -PN -v {host}

  4. Scanning a IPv6 host:

    nmap -6 IPv6-Address-Here nmap -6 2607:f0d0:1002:51::4 nmap -v A -6 2607:f0d0:1002:51::4

  5. Scan a network and find out which servers and devices are up and running

    nmap -sP 192.168.1.0/24

  6. Scanning a host quickly:

    nmap -F {host}

ONLY show open ports

nmap -F --open {host}
  1. Print packet trace on a scan:

    nmap --packet-trace {host}

  2. Doing a full nmap scan of the host requires root privelages. To invoke run this:

    sudo nmap -v -sV -sC -O {host}

This will generate a full report of services and attempt to identify OS. Good for finding admin panels and such running on hidden ports.

  1. Show host interfaces and routes:

    nmap --iflist {host}

  2. Scanning specific ports:

    nmap -p 80 {host}

    Scan TCP port 80

    nmap -p T:80 {host}

    Scan UDP port 53

    nmap -p U:53 {host}

    Scan two ports

    nmap -p 80,443 {host}

    Scan port range

    nmap -p 80-200 {host}

    Combination port scan

    nmap -p U:53,111,137,T:21-25,80,139,8080 {host} nmap -v -sU -sT -p U:53,111,137,T:21-25,80,139,8080 {host}

    Scan all ports with * wildcard

    nmap -p "*" {host}

    Scan top ports

    nmap --top-ports {number of ports} {host} nmap --top-ports {number of ports} {host}

  3. Scanning for a remote operating system:

    nmap -O -v {host}

  4. Scanning for remote services (server/daemon):

    nmap -sV -v {host}

  5. Scanning a host using TCP ACK (PA) and TCP Syn (PS) ping. Use this when a firewall is blocking standard ICMP pings:

    nmap -PS {host}

  6. Scanning a host using IP protocol ping:

    nmap -PO {host}

  7. Scanning a host using UDP ping. This scan bypasses firewalls and filters that only screen TCP:

    nmap -PU {host}

  8. Scanning a host for the most commonly used TCP ports using TCP SYN Scan:

    Stealth scan

    nmap -sS {host}

    Find the most commonly used TCP ports using TCP connect scan (warning: no stealth scan)

    nmap -sT {host}

    Find the most commonly used TCP ports using TCP ACK scan

    nmap -sA {host}

    Find the most commonly used TCP ports using TCP Window scan

    nmap -sW {host}

    Find the most commonly used TCP ports using TCP Maimon scan

    nmap -sM {host}

  9. Scanning a host for UDP services (UDP scan):

    nmap -sU {host}

  10. Scanning a host for IP protocol, this allows you to determine which IP protocols are supported by the host:

    nmap -sO {host}

  11. Scanning a firewall for security weaknesses:

    TCP Null Scan to trigger firewall to generate a response

    nmap -sN {host}

    TCP Fin scan to check firewall

    nmap -sF {host}

    TCP Xmas scan to check firewall

    nmap -sX {host}

  12. Cloaking a scan with decoys

    nmap -n -Ddecoy-ip1,decoy-ip2,your-own-ip,decoy-ip3,decoy-ip4 {host}

  13. Scanning a firewall for MAC address spoofing:

    Spoof your MAC address

    nmap --spoof-mac {your-mac-address} {host}

You can pass any other flags here as well -v -O etc…

Tools