What Is Penetration Testing and How Does It Work?

What Is Penetration Testing and How Does It Work?

9 mins read411 Views Comment
Anshuman Singh
Senior Executive - Content
Updated on Mar 27, 2024 11:45 IST

Hackers are stealing millions of documents and trillions of rupees at an alarming rate—the key to neutralizing their attempt is to conduct a thorough penetration test.


So, what is penetration testing, and how does it work? Before we answer these questions, let’s go through the topics that we will be covering in this article:

  1. What is penetration testing?
  2. What are the different stages of penetration testing?
  3. Different approaches to penetration testing
  4. Different types of penetration testing
  5. Who conducts a penetration test?
  6. Penetration testing tools
  7. Benefits of doing penetration testing
  8. Conclusion

What is penetration testing? 

Penetration testing means attempting an authorized simulated attack to exploit a system’s vulnerability in order to learn about potential flaws and the damage they can cause. As a result, in my opinion, penetration testing is a method for evaluating the safety of an application or connection by securely utilizing any security flaws in the system. Penetration testing is also called as ethical hacking or pen test.

This type of testing enables you to evaluate your security before the attacker does. Penetration testing tools replicate real-world attack circumstances in order to detect and utilize security flaws that may result in stolen data, vulnerable credentials, or other adverse business outcomes. It also helps you determine how to protect your critical information from future cyberattacks.

What are the different stages of penetration testing? 

You can think of penetration testing as a process comprising various stages. To be exact, a penetration test consists of five stages in total, which are:

Stage 1: Reconnaissance: Gather Information on the target

To plan an attack strategy first step is to collect as much information as possible about the target from both public and private sources. Your sources may include internet searches, social engineering, network topology, user accounts, operating system, and other relevant sources. This information can examine possible vulnerabilities and plan an effective attack strategy on the target. 

This stage can be categorized as active or passive depending on the information collection method. Passive reconnaissance gathers information from publicly available resources, whereas active reconnaissance requires directly engaging with the target system to gather information. In most cases, both approaches are required to provide a complete view of the target’s vulnerabilities. 

Stage 2: Scanning: Check for potential flaws 

Pen Testers use different tools to identify flaws in the target’s system or website based on the information collected on the target. This information can include checking running services, exploiting security flaws, and other open source vulnerabilities. 

After gathering all essential data during the reconnaissance phase, it’s time to start scanning. During this penetration testing phase, the Pen tester uses various tools to identify open ports and monitor network activity on the target system. Penetration testers must find as many open ports as possible for the subsequent penetration testing step since open ports are potential entry sites for attackers.

Stage 3: Vulnerability Assessment – Evaluate the data for flaws

In this third stage, the tester examines all the data obtained during the reconnaissance and scanning stages to find potential flaws to check if they can be exploited. Just like scanning, Vulnerability assessment is a helpful technique on its own but becomes more effective when integrated with the other phases of penetration testing.

Stage 4: Exploitation 

Once vulnerabilities have been found, it is time to exploit them. During this penetration testing phase, the penetration tester attempts to access the target system and exploit the found vulnerabilities, generally by simulating real-world assaults with tools like Metasploit.

This is probably the most delicate penetration testing step because accessing the target network requires bypassing security restrictions. Although system crashes during penetration testing are rare, testers must remain alert to verify that the system is not compromised or harmed.

Stage 5: Reporting

When the exploitation phase is over, the tester writes a report that summarizes the penetration test findings. The report created during this last penetration testing process may be utilized to fix any vulnerabilities discovered in the system and improve the security architecture of the firm.

The most valuable reports contain parts that provide a complete summary of discovered vulnerabilities (including CVSS scores), a business impact assessment, an explanation of the complexity of the exploitation phase, a technical risk briefing, remedial suggestions, and strategic suggestions.

Different approaches to penetration testing 

Testers use one of three approaches depending on the information available and the type of weakness to find.

White box penetration testing: The testers have complete information about the system in this type of testing. This approach aims to thoroughly test the system and collect as much information as possible.

Grey box penetration testing: The testers have little or partial information about the system in this type of testing. The advantage of this approach is that the tester has a more focused area of attack with limited knowledge, avoiding any trial-and-error method of attack.

Black box penetration testing: The testers are no information about the system in this type of testing. This approach is the most realistic and requires high technical expertise.

Different types of penetration testing 

There are various types of penetration testing, but we can categorize nearly all of them under three different types. Those three types are:

Network penetration testing

A network penetration test seeks to identify security flaws in network infrastructure, whether on-premise or in cloud environments such as Azure or AWS. It is a critical test for safeguarding your personal information and the protection of your application. External and internal penetration testing are the two types of network penetration testing. An external penetration test involves an outsider tester attacking the system with internet access and no foreknowledge of the system. The tester will try to access your system by exploiting external vulnerabilities.

On the other hand, internal penetration is more responsible for testing your application internally. In this case, the presumption is that the attackers are inside the network. Firewall bypasses, DNS footprinting, and other types of network penetration testing are examples.

Web application penetration testing

The goal is to discover critical information such as security flaws in websites, e-commerce platforms, and content management systems, among other things. This test examines the entire application to protect against data breaches and other attacks. Individuals and businesses who use web apps must run this test on a regular basis to keep up to date on the most recent attack techniques and exploitable vulnerabilities. Some of the most common vulnerabilities are network traffic and wireless encryption, MAC address forgery, DDoS attacks, etc.

Social engineering 

Human psychology is scrutinized during social engineering penetration testing. In social engineering pen testing, testers use human behavior to break into a system. Phishing attacks, tailgating, eavesdropping, and other attack methods are common.

Who conducts a penetration test?

A penetration test identifies, tests, and highlights vulnerabilities in an organization’s security posture, and ethical hackers or expert pen testers frequently perform such tests. These testers have extensive knowledge of various systems, applications, and multiple attack chains. Their strategies and methods of operation are very similar to those of an attacker and the techniques they employ.

It is also possible for an organization to hire a grey hat hacker to test the security of their systems, thereby identifying vulnerabilities that could reduce their organization’s security factor. However, hiring a grey hat hacker is uncommon in the industry; such hackers are typically hired as a last resort due to financial constraints. Hiring a grey hat hacker is less expensive than hiring an ethical hacker. Still, it is riskier because a grey hat hacker may leave vulnerabilities in order to exploit them for their gain.

Penetration testing tools 

There are many penetration testing tools and software available that a person can use to accomplish their goal. Some of those tools and software are:

Netsparker: It is a well-known automated web application tool for pen testing. The tool can identify anything, including cross-site scripting to Cross-site scripting. The tools also enable developers to create websites, web services, and web applications.

Wireshark: This software captures and interprets network packets. Wireshark also supports offline analysis and live capture and is available for various operating systems, including Windows, FreeBSD, Linux, etc.

Metasploit: This tool enables a network administrator to break into a system and identify critical flaws. It helps assess security and identify flaws in order to build a defense. This tool also verifies and manages security assessments while increasing awareness.

Indusface: The tool includes manual penetration testing as well as its own automated web application vulnerability scanner. Every scan includes a website reputation check of links, malware, and defacement checks.

John The Ripper: This tool is one of the password cracker tools available on the market, but it is one of the fastest tools in this genre. This tool is necessary for password cracking and offers a variety of systems for this purpose. This software is also free to use.

Benefits of doing penetration testing

It is crucial to conduct a pen test regularly as the technology and attacks that an attacker can use continuously evolve. So, in order to be a step ahead, you need to conduct pen tests in your organization to improve the security factor. Let’s go through some of the benefits of doing a pen test:

  • Determines the likelihood of a cyberattack
  • Keeps sensitive data safe from hackers
  • Assures that the organization is operating within an acceptable range of security risks
  • Discovers inadequate internal security policies
  • Examines the consequences of a successful cyberattack
  • Assesses the effectiveness of various security solutions
  • Prioritizes security risks into various categories, such as low, moderate, and high
  • Checks an organization preparedness for to deal with unseen events
  • Aids in the planning of preventive measures against potential cyberattacks such as SQL injection, DDoS attacks, logic bombs, and so on


One of, if not the, most complex challenges confronting cybersecurity is technological innovation. As technology advances, so do cybercriminals’ methods. Companies must be able to update their security measures at the same rate in order successfully defend themselves and their assets against such attacks. Regular pen test is one of the best ways to improve any organization’s security.

You can also explore: What is cybersecurity?


What exactly are the five stages of penetration testing?

Planning and preparation, penetration attempt, reporting and analysis, remediation and cleanup, and retest are the five phases of penetration testing.

What are the three different types of penetration testing?

Three types of penetration testing are: Black box testing White box testing Gray box testing

What exactly is the purpose of penetration testing?

This attack aims to identify any weaknesses in a system's defenses that attackers could exploit.

Who is capable of performing penetration testing?

An ethical hacker or expert pen tester can perform a penetration test to identify, test, and highlight vulnerabilities in an organization's security posture.

What is the outcome of a penetration test?

Any severe or exploitable vulnerabilities discovered during the penetration test will be aggregated into a report for the system owners.

How frequently should penetration testing be performed?

As the technology is getting advanced by each passing day and new attacks are being used by attackers, it is best that penetration testing should be performed regularly, at least twice a year.

What exactly is the VAPT procedure?

Vulnerability Assessment and Penetration Testing (VAPT) is the process of scanning for and exploiting vulnerabilities in order to assess a system's security posture.

About the Author
Anshuman Singh
Senior Executive - Content

Anshuman Singh is an accomplished content writer with over three years of experience specializing in cybersecurity, cloud computing, networking, and software testing. Known for his clear, concise, and informative wr... Read Full Bio