As penetration testers, we use open-source commercial tools, ethical hacking tools, and in-house built tools to launch simulated attacks to give our clients a proper understanding of how their defenses would hold up against a real-life cyber attack. The only difference between testers and hackers is time spent seeking exploitable vulnerabilities. Our role is to find as many vulnerabilities as possible when allotted for the engagement. In contrast, a cybercriminal can spend unlimited time examining a particular identified vulnerability, target, or potential exploit.