🤖 AI Prompts Cheatsheet
Daniel Osei — AI-Assisted Security Engineer
What is Nmap?
Nmap (Network Mapper) is an open-source tool for network exploration and security auditing. It is widely used for discovering hosts and services on a computer network by sending packets and analyzing the responses.
Installation
Nmap can be installed on various platforms. Here’s how to install it:
- Windows: Download the installer from the official Nmap website.
- Linux: Use the package manager. For Debian-based systems, run:
sudo apt install nmap
- macOS: Use Homebrew:
brew install nmap
Basic Syntax
nmap [options] [target]
Basic options include:
| Flag | Description |
|---|---|
| -sS | TCP SYN scan (default scan) |
| -T4 | Increase speed of the scan |
| -p | Specify ports to scan |
Network Discovery
IP Range Discovery
nmap -sP 192.168.1.0/24
Use this command to perform a ping scan on a subnet.
OS Detection
nmap -O 192.168.1.1
This command attempts to determine the operating system of the target.
Scanning
TCP Scan
nmap -sS -p 22,80 192.168.1.1
TCP SYN scan on ports 22 and 80.
Service Version Detection
nmap -sV -p 1-1000 192.168.1.1
Detect service versions running on the first 1000 ports.
Exploitation
Script Scanning
nmap --script vuln 192.168.1.1
This command runs vulnerability detection scripts on the target.
Analysis
Output Formats
nmap -oA scan_results 192.168.1.1
This saves outputs in all formats (XML, grepable, normal).
Evasion
Packet Fragmentation
nmap -f 192.168.1.1
This command fragments packets to evade some firewall detection.
Reporting
Saving Output
nmap -oN report.txt 192.168.1.1
Saves scan results in a text file for later analysis.
Quick Reference Table
| Flag | Description |
|---|---|
| -p | Port specification |
| -sC | Run default scripts |
| -O | Enable OS detection |
| –script | Specify script to run |
Pro Tips
- Use
-T5for the fastest scan; use cautiously, as it can be detected more easily. - Combine multiple scans using scripts to automate routine checks.
- Utilize
--top-portsto target the most common ports for efficiency.
Real-World Examples
Identifying Vulnerabilities
nmap -sV --script vuln 10.0.0.5
Invoke this command to scan a host for known vulnerabilities.
Scan and Save Result
nmap -oA save_scan 192.168.1.0/24
Conduct a scan against a subnet and save results in various formats for reporting.