Definition:

  • Network Mapper
  • Network exploration tool and security / port scanner
  • Can scan 1 device and a CIDR range
  • example
    • nmap -Pn 192.16...: ping-only scan open ports
    • nmap

Synopsis:

  • nmap [Scan Type...] [Options] {target specification}

List of options:

TARGET SPECIFICATION
HOST DISCOVERY:
  • -sn (No port scan), ping scan
PORT SCANNING TECHNIQUES:
  • -sT (TCP connect scan)
PORT SPECIFICATION AND SCAN ORDER:
  • -p <port ranges>: Only scan specified ports
    • Ex: -p22; -p1-65535; -p U:53,111,137,T:21-25,80,139,8080,S:9
  • -F: Fast mode - Scan fewer ports than the default scan
  • --top-ports <number>: Scan <number> most common ports
OS DETECTION:
  • -O: Enable OS detection
Output:
  • -oN/-oX/-oS/-oG <file>: Output scan in normal, XML, script kIddi3, and Grepable format, respectively, to the given filename.