The discovery and analysis of security vulnerabilities play important roles during a penetration test. Before a penetration tester or an ethical hacker can successfully launch an exploit, they must be able to identify the security weaknesses on the attack surface. The attack surface is the area where an attacker can attempt to gain entry to or exfiltrate data from a system. A strategic approach to quickly identifying vulnerabilities and obtaining a severity rating is to use a known and reputable vulnerability scanner.
There are many popular and reputable vulnerability scanners, such as Acunetix, OpenVAS, Qualys, Nexpose, Nikto, Retina Network Security Scanner, and Nessus, to name a few in the industry. Having knowledge about all these tools is a good idea, but you won't want to run every tool as some of these are commercial and subscription...