Nmap

Nmap (Network Mapper) is a free open source tool for network exploration and security auditing. It is used for port scanning, service identification, and vulnerability detection.

Main Features

• Port scanning (TCP, UDP)
• Service version detection
• OS detection (OS fingerprinting)
• NSE scripts (Nmap Scripting Engine)
• Firewall evasion

Scan Types

• -sS — SYN scan (stealth)
• -sT — TCP connect scan
• -sU — UDP scan
• -sV — Version detection
• -O — OS detection
• -A — Aggressive scan

Usage Examples

# Scan single host
nmap 192.168.1.1

# Scan subnet
nmap 192.168.1.0/24

# Service and OS detection
nmap -sV -O target.com

# Vulnerability scripts
nmap --script vuln target.com