Introduction

Information gathering is the first basic step towards penetration testing. This step is carried out to find out as much information about the target machine as possible. The more information we have, the better will be our chances of exploiting the target. During the information gathering phase, our main focus is to collect facts about the target machine, such as the IP address, available services, open ports. This information plays a vital role in the process of penetration testing. There are basically three types of techniques used in information gathering.

• Passive information gathering

• Active information gathering

• Social engineering

Let us take a quick look at these processes:

• Passive information gathering: This technique is used to gain information about the target without having any physical connectivity or access to it. This means that we use other sources to gain information about the target like using the whois query, Nslookup, and so on. Suppose our target is an online...