A penetration test, or pen test, is an attempt to evaluate the security of an IT infrastructure by safely trying to exploit vulnerabilities. These vulnerabilities may exist in operating systems, service and application flaws, improper configurations, or risky end-user behavior. Such assessments are also useful in validating the efficacy of defensive mechanisms, as well as, end-user adherence to security policies.

Penetration tests are typically performed using manual or automated technologies to systematically compromise servers, endpoints, web applications, wireless networks, network devices, mobile devices and other potential points of exposure. Once vulnerabilities have been successfully exploited on a particular system, testers may attempt to use the compromised system to launch subsequent exploits at other internal resources, specifically by trying to incrementally achieve higher levels of security clearance and deeper access to electronic assets and information via privilege escalation.

Information about any security vulnerabilities successfully exploited through penetration testing is typically aggregated and presented to IT and network systems managers to help those professionals make strategic conclusions and prioritize related remediation efforts. The fundamental purpose of penetration testing is to measure the feasibility of systems or end-user compromise and evaluate any related consequences such incidents may have on the involved resources or operations.