Services to test the security of an IT system. A penetration test, also called a pen test or ethical hacking, is a cybersecurity technique organizations use to identify, test and highlight vulnerabilities in their security posture. These penetration tests are often carried out by ethical hackers. These in-house employees or third parties mimic the strategies and actions of an attacker in order to evaluate the hackability of an organization's computer systems, network or web applications. Organizations can also use pen testing to test their adherence to compliance regulations.