6 Penetration Testing Methods (With Definition and Testing Stages)

Updated December 12, 2022

Penetration testing is a simulated information technology hacking attack against a company's software and security. Businesses choose to run these tests to identify weak spots in their systems so they can strengthen them and avoid malware and digital infiltration. If you're interested in penetration testing, it's important to know how it works and the different methods you can use.

In this article, we discuss what penetration testing is, six penetration methods you can implement and various phases of penetration testing.

What is penetration testing?

Penetration testing is a method for assessing the security level of a company's software and technology. Companies hire software and technology experts who attempt to attack their system to identify weak areas where an actual unauthorized user may gain access.

Penetration testing aims to discover whether a hacker can gain access to sensitive information, if they can use the technology for malicious acts, if they can introduce and spread malware and if they can access administrative profiles. These tests are used to develop software, comply with security requirements and prevent malware infections and cyber attacks. Most companies, especially those that manage client data, perform security testing regularly.

To ensure the safety and security of their personnel, clients, information and software, most companies should perform penetration testing at least once a quarter. Ensure all aspects of a system are secure by performing penetration testing on various information technology components, like the network, web applications, client access, wireless services and social engineering.

Why is penetration testing important?

Many companies hire technology and software security companies to run penetration testing. By doing this, they simulate an attempted breach without the risk so they can understand their weaknesses and vulnerabilities. These weak areas may be complications in the coding, communication errors or configuration issues. Companies use this information to strengthen their security and avoid malicious attacks and unwanted alterations. For organizations that manage sensitive client data, such as banks and healthcare providers, protecting that data is highly important to maintaining client trust and complying with privacy policies.

Companies may also use penetration testing as an opportunity to assess and train their information technology staff. By observing how the penetration tester breaches the cyber security system, the staff may be more likely to form a better defense against attackers.

There are also some methods of penetration testing in which the information technology staff is unaware that the penetration testing is happening. Evaluating how the information technology staff responds in emergency security situations is important for understanding how to improve their defensive skills and security-breach procedures. After a test, a report often includes the following elements:

Executive summary: This is an overview of the test results that generalize the security concerns concisely.

Tools and methods section: This section explains the tools and methods the hackers used to conduct the penetration tests. This section is much more technical than the executive summary, so information technology professionals may benefit most from this information.

Findings: This section outlines the security breaches the test found, explaining the various threats or security concerns. This can help the company improve certain aspects of its cybersecurity approach.

Conclusions and suggestions: The final section of a report contains the testers’ conclusions and any recommendations they have for improvement. A company can use this as a guide when they make changes after the test.

6 penetration testing methods

It is possible to perform your own penetration testing. Still, it may save you time and money to invest in penetration testing software or to hire a company that specializes in penetration testing. Many companies don't have personnel with the skills required to perform penetration testing effectively. If you're trying to evaluate the performance of your information technology security team, having your own personnel perform penetration testing may be a conflict of interest. However, there are many methods for penetration testing, including:

1. Black box

Black box testing most closely mimics a real-world hacking scenario. When companies employ this method, they don't give the tester any information about their IT infrastructure, source code or web application architecture. This method may take extended periods of time to complete.

2. White box

White box testing is the opposite of black box testing because the company gives the tester information about the system and source code. White box testing uses advanced tools like software code analyzers and debugging programs. Because of this, it may not take as long to complete as black box testing.

3. Gray box

Gray box testing is a hybrid of white box and black box testing in which the tester focuses their effort on locating weaknesses like software errors. In the gray box testing method, the tester has partial knowledge of the system. The tester may know the system architecture, but not the internal software code.

4. External

External penetration testing focuses on public-facing aspects of security. This may include the company's public internet protocols, online services and apps. When performing externally focused penetration testing, the tester identifies weaknesses in the external system, like operating architecture and service configuration.

5. Internal

In this kind of testing, the tester focuses on internal components of the company's technology and software to identify weaknesses. This may include evaluating each component of the corporate framework and the links between them. Some internal corporate framework components include servers, routers, proxies and workstations.

6. Blind

Blind testing is like black box testing, but in this method, only the security team knows about the simulated attack. In a double-blind penetration testing scenario, very few people in the company know about the test, meaning the technology defense team reacts as if it were a real cyber attack. Double-blind testing allows companies to evaluate their identification abilities, response time and defense capabilities against these kinds of technological attacks.

Stages of penetration testing

Depending on which form of penetration testing you choose, there may be different stages to the process. Some take more time, and some closely simulate a real-world attack on a company's software. Depending on the penetration testing method you choose, it may take between one to three weeks to complete the process. Regardless of which penetration method you're assessing, these are some general stages:

Penetration preparation

The first step to penetration testing is defining the goals of the test. Once the company determines what it wants to learn through the process, it can decide about which method of penetration testing to use. The company must also decide how much time it's willing to dedicate to the process, as well as how many of the company's team members should know of the upcoming test. This information is all used to develop a comprehensive test plan for when and how the penetration testing should take place. Here are a few elements to include in a test plan:

Pertinent documentation
Cyber access for relevant personnel
Contact information for primary project manager
Onboarding information
Schedule and timeline

Information reconnaissance

The second step begins with assessing basic technology information. In a black box testing situation, the tester may only have this information, but in other methods, they may have more. Preliminary technology information may include internet protocol addresses or address blocks. The purpose of this step is for the tester to learn more about the system they're attempting to infiltrate. Professional penetration testing services only perform steps involving sensitive or privileged information with the explicit consent of the company.

Discovery scanning

During this step, many testers use automated tools like software code analyzers and debugging programs to discover more about the system. This process reveals weaknesses and vulnerabilities while finding information about the network, host and service. This may include specific information like server location, open host ports and running services.

Risk analysis

Once they've assessed the preliminary information and discovered the software architecture, the tester identifies and isolates weak spots in the system. This step can be time-consuming and can include finding potential risks to the software using structured query language injection, a common hacking technique in which the tester may bypass logging in.

Intrusion attempts

Once the tester has identified several weak spots in the system, they inform the client of these aspects. The client may choose to strengthen these without testing, or they may want confirmation that they are indeed open to infiltration. If they do, the tester carefully exploits and enters the system through these vulnerabilities.

In computing, vectors are components of the system that store data. When performing this step of penetration testing, the tester may look for exploit vectors like broken authentication, weak data protection, insecure storage, improper error handling and insecure configuration. The tester may attempt to stay inside the system during counter-measures from information technology security teams within the company or business to assess their abilities.

Final analysis

The final analysis is the end of the penetration testing. The tester reports all weaknesses and vulnerabilities within the company's system. They may offer solutions for strengthening the software security at these junctions, and they may advise the company on how to avoid hacking attacks in the future. The tester discloses which sensitive data they had access to and how long they maintained access to the system during the test.

The penetration testing experts remove all accessed data created or stored during the process from any unauthorized systems. Once they've finished the penetration testing final analysis, the company can use it to invest in strengthening their information technologies system security. The company may receive other reports as part of the final penetration testing analysis, like reconnaissance scoping reports, detailed technical reports, itemized exportable reports and remediation reports.