SENG 460 – ECE 574

Practice of Information Security

& Privacy Lab

NMAP

Network Mapping

▪ Nmap is a popular tool for identifying ports in remote systems

▪ can help network, security, and developers understand how systems work

and what ports are open

▪ can scan one or many hosts with a variety of options

▪ DISCLAIMER: do not scan hosts you are not authorized to scan

Installation

▪ Nmap may not be installed on your linux system so use:

▪ sudo apt-get install nmap

▪ Nmap is also available for Windows

Nmap

▪ you can type “nmap” by itself

or “man nmap” to get help with

nmap and many parameters

▪ nmap scanme.nmap.org

scans for common ports on the specified host and identifies which ports are

open or filtered

▪ filtered means there may be a firewall in the way and nmap cannot be sure

▪ by default nmap tries to determine if the host is alive and will scan only the

most common ports

▪ nmap –Pn –p80 www.yahoo.com will disable host discovery (-Pn) and scan

Yahoo only for port 80 (-p80)

▪ scan IP addresses

▪ scan networks

▪ nmap 192.168.1.1 scan one IP

▪ nmap 192.168.1.1 192.168.1.3 scan two IPs

▪ nmap 192.168.1.1-10 scan ten IPs

▪ nmap 192.168.1.0/24 scan 255 IPs

▪ nmap –IL file.txt scan all hosts in file.txt

▪ nmap 192.168.1.1 –open only list open ports

▪ nmap -A -T4 192.168.1.1 scan with OS detection fast

▪ nmap -sV 192.168.1.1 detect server, service versions ▪ nmap –oN / -oX / -oS / -oG <file> output scan normal, XML, script

kiddie, and greppable

▪ you can use scripts with nmap to do basic vulnerability scanning

▪ eg. nmap –Pn –script vuln 192.168.1.1

Knowledge Check1. do you know what nmap is for?

2. do you know how to install nmap?

3. can you scan one IP? multiple IPs? networks?

4. can you limit the number of ports scanned?

5. do you understand you should only scan hosts you’re authorized to scan?

6. do you know how to identify operating systems?

7. do you know how to set the format of the output?

8. do you know how to limit how fast the nmap scan completes?

9. do you know how to use nmap to scan for vulnerabilities?

End of Lab