Pen testers simulate attacks by motivated adversaries. To do this, they typically follow a plan that includes the following steps:

• Reconnaissance. Gather as much information about the target as possible from public and private sources to inform the attack strategy. Sources include internet searches, domain registration information retrieval, social engineering, nonintrusive network scanning, and sometimes even dumpster diving. This information helps pen testers map out the target’s attack surface and possible vulnerabilities. Reconnaissance can vary with the scope and objectives of the pen test; it can be as simple as making a phone call to walk through the functionality of a system.
• Scanning. Pen testers use tools to examine the target website or system for weaknesses, including open services, application security issues, and open source vulnerabilities. Pen testers use a variety of tools based on what they find during reconnaissance and during the test.
• Gaining access. Attacker motivations can include stealing, changing, or deleting data; moving funds; or simply damaging a company’s reputation. To perform each test case, pen testers determine the best tools and techniques to gain access to the system, whether through a weakness such as SQL injection or through malware, social engineering, or something else.
• Maintaining access. Once pen testers gain access to the target, their simulated attack must stay connected long enough to accomplish their goals of exfiltrating data, modifying it, or abusing functionality. It’s about demonstrating the potential impact.