What is Pentest? A Complete Guide to Penetration Testing

What is Penetration Testing?

A penetration test or a pentest is a simulated cyber attack on a computer system by ethical hackers to discover and exploit vulnerabilities, mimicking real-world attackers to assess an organization’s security posture across web apps, networks, apps, and APIs.

How is a Typical Pentest Carried Out?

Beginning with reconnaissance, where testers gather information about the target system to identify potential vulnerabilities, which are exploited to gain unauthorized access. Once access is gained, testers attempt to escalate privileges and compromise sensitive data, simulating real-world attacks.

Finally, a detailed report is generated, outlining the findings, vulnerabilities, POC videos, and recommendations for remediation. Once the patches are rolled out, a rescan is also conducted to verify their effectiveness.

What Happens in the Aftermath of Pentesting?

Following the pentest, a comprehensive report is generated detailing the identified vulnerabilities, their severity, and potential impact to serve as a roadmap for the your security team to prioritize and address the issues. Remediation efforts are then initiated, involving patching systems, configuring security settings, and implementing additional security controls.

Once these measures are in place, a rescan, or two are conducted to validate the effectiveness of the patches, and a publicly verifiable pen test certificate is issued, demonstrating the organization’s commitment to security and transparency.

What are the Types of Pentests?

1. Cloud Pentest

Cloud penetration tests analyze the cloud computing environment for vulnerabilities that hackers could exploit. Based on the service model, cloud pentesting can be divided into three categories: Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS).

• IaaS cloud pentesting evaluates cloud infrastructure assets, storage, and networks.
• PaaS pentesting assesses runtime environments, development tools, and databases.
• SaaS pentesting checks how the application stores data, transmits information, and checks how it authorizes users.

Some common cloud vulnerabilities found during pentesting include insecure APIs, insecure codes, weak credentials, and server misconfigurations.

2. Network Pentest

A network penetration test aims to find vulnerabilities in the network infrastructure, either on-premise or in cloud environments such as Azure and AWS penetration testing evaluating a wide range of areas, such as configurations, encryption, and outdated security patches. 

The network pentests can be divided into internal, external, and wireless network pen testing.

• Internal network pentesting tests the organization’s internal infrastructure to ensure the security of the network’s servers, workstations, and devices.
• External network pentesting tests whether an external attacker can breach the network by conducting firewall attack vector tests and router pentests.
• Wireless network pentests assess the security of all wireless devices and channels like Wi-Fi and Bluetooth to ensure no attacker can access or alter information.

Some other network pentests conducted include DNS footprinting, SSH attacks, and evasion of IPS/IDS.

3. Web Application Pentest

Web app pen testing simulates attacks to find vulnerabilities in a web application and assess its internal and external security using three primary techniques, namely black-box, white-box, and gray-box testing. 

Some common vulnerabilities found in web app pentests include:

• Wireless encryption and network traffic
• Unprotected access points and hotspots
• Spoofing MAC address
• DDoS Attacks
• SQL/Code Injections Attacks
• Cross-Site Scripting

4. API Pentest

An Application Programming Interface (API) is a set of standards that lets applications communicate with each other. It enables developers to create customized experiences within an application.

As such, API penetration testing helps find vulnerabilities that could result in attackers getting unauthorized access to data or functions. Some of the significant security issues tested for during an API pen test are:

• Broken authentication flaws in identification measures. 
• Broken authorization due to exposed endpoints. 
• Exposure of data.
• Misconfigurations. 
• Injection flaws such as SQL, command injections, and more. 

5. Mobile Pentest

Expert penetration testers test mobile applications to find security vulnerabilities which can then be reported to the developers. Mobile pen testing applies to Android, iOS, Native, and Hybrid applications.

Some of the significant security issues found in mobile apps include:

• Lack of transport layer protection
• Insecure Communication
• Insecure Authentication
• Weak Encryption
• Lack of Binary protection.

6. Social Engineering Pentest

In contrast to testing for technological flaws, social engineering pen testing concentrates on testing and exploiting human deficiencies. It evaluates an organization’s vulnerability to social engineering techniques by simulating attacks to test the people within the organization.

Using these techniques, penetration testers can evaluate an organization’s ability to fend off social engineering assaults and pinpoint areas where security awareness policies and training need strengthening. Standard social engineering techniques include:

• Phishing
• Pretexting
• Tailgating
• Impersonation

Penetration Testing Stages

1. Planning and Scoping:

Before diving into the technical aspects, the pen test team meticulously plans the entire operation, including defining clear objectives, such as identifying vulnerabilities or simulating real-world attacks. Moreover, gathering publicly accessible data about the target system, encompassing its infrastructure, applications, security measures, and more, helps improve efficiency.

2. Vulnerability Assessment:

Using a combination of automation and manual techniques, pentesters meticulously scan and analyze the target system with a keen eye for weaknesses, such as outdated software, misconfigurations, SQL injections, or insecure coding practices, prioritizing the most critical risks.

3. Exploitation:

With a clear understanding of the target system’s vulnerabilities, the penetration testing team simulates real-world attacks to exploit these weaknesses in an attempt to gain unauthorized access, escalate privileges, or compromise sensitive data. Every successful and unsuccessful attempt is meticulously documented, including the techniques used and the system’s behavior.

4. Reporting:

After exploitation, they compile a comprehensive report detailing their findings, providing a clear and concise overview of the identified vulnerabilities, their potential impact, and practical recommendations for remediation. By providing actionable insights, they empower you to strengthen your security posture and protect valuable assets.

5. Post Exploitation:

To ensure the effectiveness of the remediation efforts, a re-scan is offered to verify that vulnerabilities have been successfully mitigated and the security posture has improved. In some cases, security testing companies issue a formal certification or report to demonstrate the system’s security compliance.

Pen Testing Methods

There are three main types of pen testing methods adopted by testers; the key differences in these approaches are based on the information available and the types of weaknesses to be identified:

1. White Box Pen Testing

In a white box pen test, the pentesters have complete knowledge of and access to information about the system. Moreover, since they have unbridled access and knowledge of the system, including code base code quality, API documentation, and internal designs, the pentest can identify even remotely located vulnerabilities, thus giving a nearly complete picture of the security.

2. Black Box Pen Testing

In this case, the pentester does not know the system and designs the test as an uninformed attacker. Conducted by a third party, it requires the pentester to think outside the box and employ methods that a true hacker would use to break into a system, facilitating detection, exposure, and exploitation of vulnerabilities to their fullest extent.

3. Gray Box Pen Testing

As the name suggests, this approach combines white-box and black-box penetration testing, i.e., the tester only has limited knowledge of the system.  This approach simulates a more realistic attack scenario, where an attacker may have some insider knowledge or has already breached the initial perimeter allowing for a more focused yet efficient pen test.

Why is a Penetration Testing Important?

Here are the 8 key benefits of penetration testing for securing your business:

1. Identification of Vulnerabilities:

Penetration testing helps identify vulnerabilities in computer systems, networks, and applications that attackers can exploit. This allows organizations to prioritize and fix these vulnerabilities before exploiting them.

2. Enhanced Security:

Pentesting helps organizations enhance their security posture by identifying potential security gaps and improving security controls.

3. Meeting Compliance Requirements:

Many regulatory and industry standards require regular penetration testing to ensure that organizations meet security requirements. For example, the Payment Card Industry Data Security Standard (PCI DSS) requires regular penetration testing of networks and applications that process credit card data.

4. Cost-Effective:

Penetration testing helps identify potential security threats cost-effectively, allowing organizations to identify and fix security issues before they become major security incidents.

5. Build Trust:

Having a pentest certificate and compliance achievements requiring pentesting showcase to customers and partners that you’re committed to high-security standards. This builds trust.

6. Protect Company and Employee Data:

By regularly conducting penetration tests, you can prevent data breaches and safeguard all employee and customer data.

7. Improve Reputation:

Displaying commitment to security via pentesting can be very beneficial for your organization’s overall reputation and attracting new customers and partners.

8. Prevent Financial Loss:

The average cost of a data breach in 2023 was found to be USD $4.45 million. By employing preventive measures like pentesting, you can prevent exorbitant financial and reputational losses caused by breaches.

These are just a few reasons penetration testing is valuable for maintaining asset security.

Who Performs Pen Testing?

Cybersecurity experts with an extensive understanding of exploitation strategies and security flaws conduct pen testing. These professionals, called pen testers, use a systematic approach to simulate real-world hacker behavior to find vulnerabilities that can be exploited.

Although some companies employ in-house security teams to conduct this testing, many hire external VAPT (vulnerability assessment and pen testing) companies. These security service providers have wider expertise, an objective viewpoint, and access to cutting-edge technologies and procedures.

Why Astra Pentest?

1. Hacker Style Pentest

Astra’s 10x security engineers with industry-standard certifications perform a hacker-style pentest to ensure no vulnerability remains unturned. AI powers Astra’s platform to ensure complete coverage by creating tailored test cases for your application.

2. Continuous Pentest Platform

Keep up with the 50+ new vulnerabilities discovered daily by Astra’s continuous vulnerability scanner. This scanner integrates into your CI/CD pipeline to ensure that every new feature you build is scanned for vulnerabilities.

3. Compliance with Security Standards

You stay compliance-ready by tackling vulnerabilities that could have hindered your compliance effort. Auditors of SOC2, HIPAA, ISO27001, etc, accept our pentest report.‍

4. Security Means More Trust

By staying secure and compliant, you build trust and credibility that translates into increased revenue.

Final Thoughts

Penetration testing is a critical part of a holistic cybersecurity policy. Proactively identifying and patching vulnerabilities will help an organization significantly reduce the risk of breaches and financial losses.

However, the increased occurrence of cyber-attacks has made it necessary for organizations to conduct regular penetration testing to mitigate these threats.

While pentesting is necessary, an organization must know that this is just one piece of a comprehensive security puzzle. Penetration testing in other security measures requires employee training, network monitoring, and incident response planning.

Pentest FAQs

Explore Our Penetration Testing Series

This post is part of a series on penetration testing.
You can also check out other articles below.

Chapter 1: How to Do Penetration Testing the Right Way (5 Easy Steps)?
Chapter 2: Different Types of Penetration Testing
Chapter 3: Top 5 Penetration Testing Methodology to Follow in 2025
Chapter 4: Ten Best Penetration Testing Companies and Providers
Chapter 5: Best Penetration Testing Tools Pros Use – Top List
Chapter 6: A Super Easy Guide on Penetration Testing Compliance
Chapter 7: Average Penetration Testing Cost in 2025
Chapter 8: What is Penetration Testing Report?