Nmap: Network Exploration and Security Auditing Cookbook - Second Edition (2024)

FAQs

How is Nmap used for auditing? ›

Nmap is an open-source utility for network discovery and security auditing. Nmap uses IP packets to determine such things as the hosts available on a network and their services, operating systems and versions, types of packet filters/firewalls, and so on. audit server interface exclusively for network port scans.

Internet security companies can use Nmap to scan a system and understand what weaknesses exist that a hacker could potentially exploit. As the program is open-source and free, it is one of the more common tools used for scanning networks for open ports and other weaknesses.

Nmap is a powerful tool for ethical hackers who want to scan and analyze network traffic and logs. It can help you discover hosts, ports, services, vulnerabilities, and other information about your target network. But like any tool, it has its advantages and disadvantages.

What is Nmap? Nmap is a network scanning tool—an open source Linux command-line tool—used for network exploration, host discovery, and security auditing. Gordon Lyon (pseudonym Fyodor Vaskovich) created it to help map an entire network easily and find its open ports and services.

When used properly, Nmap helps protect your network from invaders. But when used improperly, Nmap can (in rare cases) get you sued, fired, expelled, jailed, or banned by your ISP.

Nmap is not only a powerful and versatile tool, but it runs directly from the command line in Windows, Linux, and even macOS. Nmap is used far and wide —and can be seen on screen being used by TV and movie hackers.

Nmap sends TCP packets with specific characteristics, probes to the target host and determines the OS based on the host's responses. Advanced options of the scan can also detect the specific OS version and potential security risks. This information is useful during network reconnaissance.

Nmap sends packets to ports, monitors responses and then tags the ports as open, closed, or perhaps protected by a firewall. Port scanning is a method of ascertaining which ports on a network may be open and involved with sending or receiving data. Port scanning is also referred to as port discovery or enumeration.

Using Nmap

Nmap allows you to scan your network and discover not only everything connected to it, but also a wide variety of information about what's connected, what services each host is operating, and so on. It allows a large number of scanning techniques, such as UDP, TCP connect (), TCP SYN (half-open), and FTP.

How can Nmap be used by threat actors? ›

Attackers use Nmap to scan large networks quickly by using raw IP packets to identify available hosts and services on the network and determine their vulnerabilities. Hackers and pen testers typically add specific options to cover their tracks.