What is the main difference between vulnerability scanning and penetration testing?

The distinction between vulnerability scanning and penetration testing is fundamentally rooted in their objectives and approaches. Vulnerability scanning is primarily a process that involves identifying potential vulnerabilities in a system or network through automated tools. It provides a comprehensive overview of security weaknesses that could be exploited, including unpatched systems, misconfigurations, and outdated software. This identification is crucial as it helps organizations recognize areas that require attention before they can be attacked.

On the other hand, penetration testing goes a step further by not only identifying these weaknesses but also attempting to exploit them to assess the extent of the vulnerabilities and the effectiveness of security measures in place. This process is often more manual and involves skilled testers who simulate real-world attacks to understand how far an attacker could penetrate into a system or network. The main focus here is on not just the identification of vulnerabilities, but also the evaluation of the potential impact of those vulnerabilities if they were to be exploited.

Thus, the main difference lies in the scope: vulnerability scanning serves as an initial reconnaissance effort to find weaknesses, while penetration testing involves actively attempting to breach those weaknesses to understand their exploitability and to measure the organization's security posture comprehensively.