Security testing is a technical assessment used to find weaknesses in software, cloud services, networks, and infrastructure, and to verify that security controls work as intended. It can include vulnerability scanning, configuration review, penetration testing, authentication checks, and validation of protections such as access control, logging, and segmentation.
It matters because security controls can fail after deployment, change during updates, or be bypassed by attackers. Regular testing helps defenders spot exposed services, weak passwords, insecure APIs, misconfigurations, and missing patches before an adversary does. In real attacks, many breaches begin with issues that testing should catch early, such as unpatched systems or overly broad permissions. In defense, security testing supports continuous assurance by providing evidence that controls are effective, not just documented. Good programs define scope, use safe methods, and combine automation with human review so testing improves resilience without disrupting production systems.