Skip to content
Knowledge base Updated: May 17, 2026

Types of Penetration Testing: How to Choose?

Types of penetration testing from nFlo: how to choose the right test? Increase the security of your IT infrastructure.

In today’s complex and dynamic cyber environment, information security has become a key priority for companies worldwide. Conducting penetration tests is one of the most effective ways to identify and eliminate security vulnerabilities in IT systems. Penetration tests, also known as pentests, simulate real attacks on company systems in a controlled manner, enabling evaluation and improvement of security measures. In this article, we will discuss different types of penetration tests and indicate how to choose the right type for your company.

What Are Penetration Tests?

Penetration tests are controlled and safe attacks on IT systems, aimed at identifying potential weaknesses and security vulnerabilities. During a pentest, ethical hackers – security specialists – simulate cybercriminal attacks to discover weak points that could be exploited for unauthorized access, data theft, or system disruption. The results of penetration tests provide the company with valuable information that allows for implementing appropriate countermeasures and increasing the level of protection against real threats.

📚 Read the complete guide: Cyberbezpieczeństwo: Kompletny przewodnik po cyberbezpieczeństwie dla zarządów i menedżerów

Analysis of Different Types of Penetration Tests

There are three main types of penetration tests: white-box testing, black-box testing, and grey-box testing. Each of these types differs in methodology, scope, and level of knowledge about the system that the tester possesses. Below we present a detailed analysis of each of these types.

1. White-box Testing

White-box testing, also known as clear-box or glass-box testing, is an approach where the tester has full knowledge of the tested system. This includes access to source code, architectural documentation, and network configuration. Thanks to this, the tester can conduct a very thorough and comprehensive analysis of the system, identifying both obvious and hidden security vulnerabilities.

Advantages:

  • Deeper system analysis, enabling detection of even the most hidden vulnerabilities

  • High test accuracy, thanks to full knowledge of the system

  • Ability to conduct tests at various levels, from application to network infrastructure

Disadvantages:

  • Requires significant time and resources, which may involve higher costs
  • Testers must be highly qualified and well-acquainted with the system

When to Use:

  • When the company wants to thoroughly analyze its system for vulnerabilities
  • During internal audits and security assessments before introducing new systems or applications

2. Black-box Testing

In black-box testing, the tester has no knowledge of the internal structure of the system. They act like an external attacker, trying to find and exploit security vulnerabilities without prior knowledge of the system. This test simulates a real external attack scenario, allowing assessment of security measures available to potential hackers.

Advantages:

  • Real attack simulation, enabling realistic assessment of system vulnerability

  • Less time-consuming and usually cheaper than white-box testing

  • Focus on external vulnerabilities that can be exploited by cybercriminals

Disadvantages:

  • Limited depth of analysis, which may overlook internal security vulnerabilities
  • Testers may not be able to discover hidden problems known only internally

When to Use:

  • For testing external system security
  • When the goal is to assess vulnerability to external attacks

3. Grey-box Testing

Grey-box testing is a compromise between white-box and black-box testing. The tester has limited knowledge of the system, usually including general architecture and some detailed information. This type of test combines the advantages of both approaches, offering a balance between accuracy and realism.

Advantages:

  • Balance between accuracy and realism, allowing for effective analysis

  • Ability to detect both external and internal security vulnerabilities

  • Less time-consuming and costly than white-box testing

Disadvantages:

  • May be less accurate than white-box testing
  • Less realistic than black-box testing when it comes to simulating real attacks

When to Use:

  • When the company wants a realistic test with a certain level of detail
  • During regular security audits and compliance assessments with industry regulations

How to Choose the Right Type of Penetration Test?

Choosing the right type of penetration test depends on several key factors, including business objectives, resources, and IT system specifics. Below we present the most important aspects to consider when making a decision.

1. Business and Security Objectives

First of all, business and security objectives should be defined. Is the goal a full system analysis, simulation of a real attack, or perhaps a balance between accuracy and realism? Based on this, you can decide which type of test will be most appropriate.

2. Resources and Budget

Penetration tests can be expensive, so it’s important to consider available resources and budget. White-box testing, although most accurate, is also most expensive. Black-box testing is cheaper but less accurate, and grey-box testing is a compromise, offering moderate costs with a satisfactory level of analysis.

3. IT System Specifics

The characteristics and scale of the IT system also affect the choice of test type. Large and complex systems may require more detailed analysis, while smaller systems may be adequately tested using black-box testing.

4. Regulations and Industry Requirements

Some industries have specific requirements for penetration testing. For example, the financial sector may require more rigorous tests, such as white-box testing, while other industries may be satisfied with grey-box or black-box testing. It’s important to be aware of these requirements and adapt the testing strategy to applicable regulations.

Summary

Choosing the right type of penetration test is crucial for ensuring effective protection of the company’s IT systems. White-box testing offers the deepest analysis, black-box testing simulates real attacks, and grey-box testing is a compromise between accuracy and realism. When choosing the appropriate test, business objectives, resources, system specifics, and industry requirements should be considered. By conducting the appropriate penetration test, the company can effectively identify and eliminate security vulnerabilities, protecting its data and resources from cybercriminals.

Learn key terms related to this article in our cybersecurity glossary:


Learn More

Explore related articles in our knowledge base:


Explore Our Services

Need cybersecurity support? Check out:

Pentest pillar cluster

Share:

Talk to an expert

Have questions about this topic? Get in touch with our specialist.

Sales Representative
Grzegorz Gnych

Grzegorz Gnych

Sales Representative

Response within 24 hours
Free consultation
Individual approach

Providing your phone number will speed up contact.

Want to Reduce IT Risk and Costs?

Book a free consultation - we respond within 24h

Response in 24h Free quote No obligations

Or download free guide:

Download NIS2 Checklist