Building a strong pentesting methodology

To stay ahead of cybercriminals, you have to think like them. Penetration testing, also known as pentesting, is a method of evaluating the security of networks, systems, and applications by attempting to penetrate their defenses in ways that mimic the tactics used by malicious attackers. 

Cybersecurity experts known as ethical or white hat hackers use techniques, tools, and mindsets employed by cybercriminals to locate potential weaknesses in a network and exploit them via simulated attacks. These experts may use everything from social engineering (such as phishing attempts to gain valid security credentials) to unpatched security vulnerabilities to gain access to a network or device. 

Ethical hackers and their clients use different methodologies to guide their planning and actions during the pentesting process. These methodologies serve as an important framework and should be chosen carefully with the pentesting context and objectives in mind.  

Why is pentesting methodology important in cybersecurity?

The goal of pentesting is to proactively identify any potential weaknesses and address them before malicious actors can detect and take advantage of them. Even the most well-thought-out cybersecurity plan can have unexpected vulnerabilities or weak points. Plus, what works in theory doesn’t always align perfectly with what happens in reality.

Opting for an established pentesting methodology versus trying to build your own testing processes helps ensure the pentesting process is comprehensive, organized, thorough, and accurate. A given methodology can be used to engage in pentesting of network infrastructure, web applications, mobile devices, wireless networks, and even physical facilities.

Pentest methodologies can help ensure that critical aspects of cybersecurity are covered before, during, and after the exercise. For example:

  • Compliance. Penetration testing methodologies may be used to maintain and align with security regulations and standards in different industries.
  • Testing for incident response. Many pentesting methodologies enable the measurement and documentation of how organizations respond to different types of incidents and attack vectors, and how well team members follow established procedures. 
  • Continuous improvement. Using a pentest methodology helps organizations learn from mistakes and build up defenses against evolving threats on an ongoing basis, making its cybersecurity strategy and framework more resilient.

Failing to use a solid pen testing methodology can compromise the entire exercise, wasting resources and time. Negative consequences can include:

  • Disorganization. A pentesting methodology framework clearly defines the goals of the exercise and details every step. Without documenting the process, stakeholders may not understand the value or point of the exercise.
  • Incomplete coverage. Not using a methodology runs the risk of haphazard testing that can miss systems, devices, or other critical areas of the infrastructure.
  • Inefficiency. A penetration testing methodology helps ensure that you are allocating resources most effectively and in a way that will provide you with the insights that you need.
  • Invalid or inconsistent results. Without a methodology, you may not be able to duplicate or validate your findings or use them to track security improvements over time.

It may be tempting to think of a penetration test methodology as a “nice to have” in your clients’ cybersecurity plans. However, the consequences of skipping it can result in an inaccurate or incomplete pentesting process. Learn more about how to build a robust and resilient cybersecurity plan for your clients with our e-book, The Ultimate Operations Guide for MSP Cybersecurity.

Pentesting methodology types

It’s important to understand the different pentesting methodology options so you can choose the most appropriate and effective one for you and your clients. 

These are the five most common types of pentest methodologies and their different approaches, features, and capabilities.

  • Open-Source Security Testing Methodology Manual (OSSTMM): Developed by the Institute for Security and Open Methodologies (ISECOM) in 2000, OSSTMM is one of the most popular penetration testing methodologies. It takes a holistic approach to pentesting that encompasses wireless, telecommunications, and data networks, as well as humans and physical facilities. Its value lies in its scientific method, which can also be adapted for specific needs and environments.
  • Open Web Application Security Project (OWASP): This is a set of resources, tools, and guidance developed and maintained by members of the cybersecurity community to incorporate new and emerging threats. The group maintains a “top ten” list of critical web application security lists and a testing guide with detailed instructions for engaging in pentesting. 
  • National Institute of Standards and Technology (NIST): As one of the most rigorous standards of security, NIST provides a highly specific pentest methodology, especially for organizations that want to maintain compliance with NIST certifications, such as those that work with federal agencies. It offers detailed guidance for policies, roles, and techniques in pentesting; validation of vulnerabilities; security assessment planning and execution; and procedures for corrective actions.
  • Penetration Testing Execution Standards (PTES). This penetration test methodology was designed by information security professionals to provide consistent standards, a systematic structure, and a baseline for pentesting. It identifies seven stages of pentesting, from pre-engagement planning to remediation. While it has not been updated to reflect more recent developments in technology, such as Cloud environments, it is still in frequent use as a baseline and general framework.
  • Information System Security Assessment Framework (ISSAF). This guide, supported by the Open Information Systems Security Group, connects its main steps with tools and goals to empower organizations to create a pentesting plan that aligns with their specific needs. Unlike many other penetration testing methods, it offers technical guidance on carrying out pentesting activities. 

How to choose a pentesting methodology

Choosing an appropriate pentesting methodology depends on a multitude of variables. Some factors you should consider include:

  • Industry compliance requirements. Organizations may have to meet certain standards for security, such as HIPAA or ISO, for which certain methodologies may be more effective. Some industries may even mandate a specific methodology.
  • Organizational alignment. The pentest methodology should align with the organization’s size, security requirements, and technology infrastructure and environment. Some methodologies may be more appropriate for smaller organizations, others for large and complex enterprises.
  • The nature of potential threats. The methodology should enable and support testing for the most likely risks the organization or the particular technology environment will face.
  • Testing goals and depth. Penetrating testing that is limited to a certain aspect of a network or to look for specific types of threats may be able to use a simpler methodology, while more comprehensive testing may require a more detailed methodology with more steps.
  • Available resources. Budget and time considerations can also help organizations identify which methodology is best for their pentesting exercise.
  • Transparency. A robust methodology with detailed guidelines, technical instructions, and reporting practices supports clearer communication and understanding among testing participants and stakeholders. 

Stages of the pentesting process

Different pentest methodologies divide testing into phases slightly differently, but there are some main categories.

    1. Preparation: It’s critical to identify and understand the goals of the testing, define its scope (including the target system, network, or applications), outline limitations, and lay out the rules of engagement. MSPs help the client choose which components of their infrastructure would benefit most from pentesting and define their objectives.  
    2. Information gathering: The hacker conducts reconnaissance activities to gather as many details as possible about the target environment. They may use publicly available information as well as information gathered from network scanning and fingerprinting, such as the operating system and type of network topology in use. You shouldn’t do anything to assist the hacker, as the point of pentesting is to find out what they can do on their own.
    3. Scanning. The hacker uses different tools to scan the target for possible areas of attack, such as open ports, unpatched security vulnerabilities, or unsecured communications channels, such as Bluetooth. MSPs may be able to detect scanning attempts, which would validate the effectiveness of defenses in place and force the hacker to find other potential openings. 
    4. Vulnerability assessment. In this phase, the hacker uses the information they have gathered to identify which areas of entry have the most potential for exploitation or attack. They often use an automated vulnerability scanner to uncover weaknesses in the technical infrastructure as well as evaluate the vulnerabilities posed by human factors, such as weak password policies or susceptibility to phishing. Hopefully, you have worked with your clients to ensure security defenses and patches are up-to-date and train employees on best practices for passwords and recognizing social engineering tactics.
    5. Exploitation. Once the hacker has identified some vulnerabilities with a high chance of success, the testing begins. The tester attempts to gain access to the target environment by leveraging the weak points. You may be able to pick up on signs of intrusion during the exercise and engage in defensive techniques to fight it off, forcing the hacker to try to exploit a different vulnerability.
    6. Reporting. Once the exploitation attempts are complete, the hacker creates an extensive report detailing the tools and tactics they used, the vulnerabilities they found, what they were able to access and do within the target environment, and the potential implications of their findings. They also suggest where you can strengthen cybersecurity measures to prevent similar attacks. This documentation can provide a road map of concrete actions for improved security planning and strategies.
    7. Remediation. After evaluating the suggestions in the tester’s report, you can create an action plan for addressing them according to priority level, available resources, and your clients’ overall security needs. The tester may be able to work with you to provide additional insights and guidance as well as provide a follow-up to ensure remediation efforts were successful.

Best practices for implementing pentesting

Penetration testing can be a significant effort that requires extensive resources, so abiding by best practices can help ensure the process goes smoothly and that the outcome is as beneficial as possible.

  • Use a credible and trusted pentesting team. These professionals should have an established and extensive background in cybersecurity as well as a positive reputation and reviews. Certifications like Certified Ethical Hacker (CEH), Offensive Security Certified Professional (OSCP), or Certified Information Systems Security Professional (CISSP) can also be valuable for providing evidence of knowledge and skills.
  • Research laws and industry regulations that may apply to penetration testing, such as GDPR and HIPAA legislation for data privacy.
  • Establish detailed rules of engagement that define what actions are permitted, methods that can be used, authorizations that are needed, legal and ethical guidelines, and any areas or methods that are off-limits or otherwise limited.
  • Communicate with clients before, during, and after the penetration testing exercise to explain how the test will work, provide updates, and share any issues that arise.

Supporting pentesting methodology with cybersecurity solutions

High-quality cybersecurity solutions support pentesting methodology best practices and ensure that your pentesting is thorough and accurate. Designed and updated by information security experts to reflect a dynamic threat landscape, they can help you prepare for pentesting as well as fix any issues identified during the exercise.

Some features to look for include:

  • Alignment with pen testing methodologies
  • Tools, workflows, and other features that facilitate testing and ensure systematic and thorough coverage 
  • Exploitation frameworks and web application testing to help ensure that testing is comprehensive and in-depth
  • Documentation and reporting functionalities to capture data, clearly communicate findings, and show compliance with industry regulations and standards
  • Capacity to manage different levels of pentesting depth and complexity
  • Integration with other tools and platforms to enable efficient sharing of data 

ConnectWise offers a suite of cybersecurity management solutions designed to help MSPs deliver exceptional security outcomes, powered by a best-in-class security tech stack. Watch an on-demand demo today to see how our cybersecurity solutions can help your MSP deliver the security protection your clients demand.


A pentest methodology is a structured framework or approach for exercises in which ethical hackers seek to gain access to a network, application, or system so that an organization can proactively identify and address security vulnerabilities. Choosing the right penetration testing methodology helps ensure that the entire testing process is comprehensive, meaningful, and accurate.

Steps in each type of pen test methodology can vary, but the basic steps are:

  • Preparation and planning
  • Reconnaissance and information gathering
  • Vulnerability scanning and assessment
  • Exploitation (the actual attempts at access)
  • Reporting and documentation
  • Remediation of identified issues

Penetration testing methods help ensure that the entire testing process is organized, efficient, and accurate. They also serve as guidelines for all stakeholders and ensure that everyone understands and is informed about the process. Having a systematized methodology is also valuable for consistency and reproducing results for quality assurance.

Pentesting methodology and the testing itself should be completed by professional cybersecurity experts with specialized knowledge of hacking techniques and tools. Often these professionals carry industry certifications, such as Certified Ethical Hacker (CEH), Offensive Security Certified Professional (OSCP), or Certified Information Systems Security Professional (CISSP). They should also be committed to and be able to show evidence of objectivity and ethical conduct at all times.

Penetration testing methodologies require different tools at different points. Here are some potential tools at each stage of a typical methodology:

  • Planning and preparation: Communication and documentation tools such as Zoom, Microsoft Office, and Google Workspace
  • Information gathering: Network mapping, port scanning, and email harvesting tools
  • Vulnerability assessment: scanners for web servers, networks, and systems
  • Exploitation: Frameworks and testing tools that simulate real-world attacks; password cracking tools; network traffic analyzers
  • Reporting and documentation: Presentation software, data visualization applications