Hackers use packet analysis to sniff network traffic in order to gain valuable information about the network as a precursor to an attack. Sometimes called a passive attack, a hacker can use Wireshark to sniff network traffic with the goal of obtaining sensitive information. In addition, hackers can use the information gathered to launch an active attack.

As a precursor to an attack, hackers gather information during reconnaissance, which is also called footprinting. The goal of reconnaissance is to gather as much information about the target as possible. Let's take a look at a couple of ways in which hackers use Wireshark as part of a passive attack.