What is Pentesting or Penetration Testing? Definition, types, and how to implement it in your business

Do you really know what pentesting is and how it can protect your company from cyberattacks? This technique aims to prevent vulnerabilities before cyberattackers can exploit them. With these penetration tests, organizations can detect and strengthen weak points in their systems, preventing potential data loss and financial damage.

In this article, we'll tell you in depth what pentesting is all about, its types, when to perform these tests, and other related topics.

What is pentesting and what is its purpose?

The pentesting, also known as pentest or penetration test, is a technique used to identify and evaluate vulnerabilities in a company's IT systems. It involves simulating real attacks in a controlled manner to uncover potential security flaws before cyberattackers can exploit them. In other words, it's a test that involves attacking different access points to an infrastructure to detect and prevent potential flaws or attacks.

{{body-cta-1}}

The word comes from the abbreviation formed by combining the words "penetration" and "test," which in English means "penetration" and "test."

With pentesting, companies proactively address potential cyberattacks by identifying weaknesses. Through this test, organizations can detect security breaches in web applications, unauthorized access to databases, and exposure of sensitive information.

Now that you know what pentesting is, you might be wondering who performs these penetration tests? The answer is: the pentester. We'll explain it in the next section.

What Does a Pentester Do?

Pentesters pentesters, also known as ethical hackers, are cybersecurity professionals who specialize in evaluating the security of an organization's computer systems and networks. In other words, they conduct planned, real-world attacks on systems to find technological weaknesses before cybercriminals do. Their main functions include:

• Conduct controlled and authorized attacks on systems to identify security vulnerabilities and weaknesses.
• Utilize specialized tools and techniques to scan ports, search for known vulnerabilities, and exploit security flaws.
• Analyze application and system code to identify potential weak points.
• Apply social engineering techniques to assess employee resilience against potential manipulation or deception attacks.
• Document findings and provide detailed recommendations to strengthen security and mitigate risks.
• Collaborate with system owners to implement necessary corrections and improve overall security.

What are the functions of pentesting?

In addition to identifying vulnerabilities, penetration tests are also used to ensure compliance with a specific security policy, or for the company to align with the controls of standards such as ISO 27001 or SOC 2. This is achieved by understanding employee awareness of the policy and identifying the organization's ability to respond to such incidents.

It's worth noting that, during contracted Security Assessments, detected vulnerabilities are reported to system administrators so they can implement the necessary corrections to mitigate security breaches. This helps reduce the number of attack vectors that a cyberattacker could exploit in a real environment to obtain valuable information and use it for malicious purposes.

Once corrections have been implemented, retesting is performed, where tests are run again to validate that the corrections have been successfully implemented. However, we will discuss all the stages of a penetration test in more detail later.

When should pentesting be performed?

It is recommended to conduct at least 2 penetration tests per year on a company's most critical systems, or when significant changes have occurred in the architecture or logic. This ensures the security of applications, guaranteeing that no new security breaches have developed that could be exploited by cyberattackers or hackers to gain unauthorized access to systems.

Benefits of Pentesting

Conducting penetration tests or pentesting in your organization not only helps detect vulnerabilities but also comprehensively strengthens your enterprise cybersecurity strategy. Here are the main benefits of conducting a professional pentest:

1. Proactive Identification and Remediation of Vulnerabilities

‍Pentesting allows you to discover technical and configuration weaknesses before cybercriminals can exploit them. This way, IT teams can remediate the findings, and through retesting, confirm that there are no longer any critical findings.

2. Compliance with Regulations and Standards

‍Many regulations, such as ISO 27001, PCI DSS, SOC 2, or financial regulations, require periodic security tests. Pentesting helps demonstrate compliance to clients, auditors, and regulators through a validation report that certifies your company's infrastructure is free of vulnerabilities. ‍

3. Technical and Management Team Awareness

Pentesting results include a technical and executive report, which allows the IT team and senior management to clearly understand the real risks of their infrastructure. This information promotes a more conscious cybersecurity culture, helps prioritize investments, and enables strategic decision-making based on real data, not assumptions.

4. Reduction of Financial Risks

A security breach can cost millions in losses, fines, reputational damage, and customer churn. Pentesting acts as a tool for preventing costs associated with cybersecurity incidents. By investing in regular penetration testing, operational continuity is protected, and the financial impact of a potential attack is significantly reduced.

Discover the best pentesting companies here

What are the types of pentesting?

There are several ways to classify penetration tests or pentesting. Here, we will cover both the scope types and the types of technologies they cover.

Pentesting by Box Type (Scope)

There are three box types:

Black box pentesting or black box

Black box pentesting is an attempt to compromise the IT system without prior knowledge. This test reveals errors or security flaws in the application that could be exploited by a cybercriminal performing external attacks, without system access. Only the application's URL or IP address is provided. Test cases are limited, as the application's internal functionality is not exploited.

Grey box pentesting or grey box

In this box test, certain confidential information is provided about the application, such as access credentials and an architectural overview. This helps expand the test cases to be executed, which often leads to the discovery of more critical and significant security vulnerabilities.

{{body-cta-2}}

Specific parts of the application are attacked in a highly targeted manner. It has all the benefits of a black box test; however, it takes longer, as external and internal attacks are carried out by simulating the role of an authenticated user.

White box pentesting or white box

During white box pentesting , complete confidential information about the application and system is provided, including its architectural design, access credentials, and most importantly: the source code is shared for a full review to uncover even more vulnerabilities. 

This is the most comprehensive test, as it provides a complete security audit of the system; however, it is the most time-consuming to perform due to its high complexity.

‍

Pentesting by Technology Type

In this section, we will cover the types of technologies that can undergo pentesting, such as networks, servers, applications (web, mobile, desktop, and hybrid), DDoS, cloud, firewalls, and source code.

Network Pentesting

The network pentesting involves evaluating the security of an organization's communication infrastructure, identifying vulnerabilities that could allow an attacker to access, manipulate, or disrupt network services. This type of test focuses on devices, protocols, and configurations that support daily operations, whether in internal networks (LAN) or external networks (WAN, Internet).

{{body-cta-3}}

Main Objectives

• Identify insecure configurations in routers, switches, firewalls, and other devices.
• Detect exposed services that should not be publicly accessible.
• Evaluate protocols and encryption used to ensure information confidentiality and integrity.
• Simulate real-world attacks such as sniffing, spoofing, or lateral movement within the network.
  

Typical Scope

• Internal Network: testing from the perspective of an authorized user or an intruder who gained physical or logical access to the LAN.
• External Network: testing simulating attacks from the internet, evaluating perimeter firewalls, VPNs, and exposed services.
• Hybrid Environments: cloud and on-premise scenarios with secure interconnections.
  

Server Pentesting

server pentesting focuses on evaluating the security of systems hosting applications, critical services, and databases. The goal is to identify vulnerabilities in the operating system, installed software, configurations, and permissions, to prevent unauthorized access or data compromise.

Main Objectives

• Detect operating system vulnerabilities (Windows Server, Linux, BSD, etc.).
• Review insecure configurations in services such as HTTP, FTP, SSH, RDP, databases, and mail servers.
• Identify outdated software with known security flaws.
• Verify privilege segregation and security in user accounts and passwords.
• Evaluate sensitive data exposure in files, logs, or databases.
  

Typical Scope

• Internal Servers: in on-premise environments or corporate data centers.
• External Servers: located in the cloud (AWS, Azure, GCP, etc.) or public hosting.
• Critical Servers: that support services such as ERP, CRM, customer databases, or industrial control systems.

Web Application Pentesting

The Web application pentesting focuses on evaluating the security of websites, portals, and browser-accessible systems, identifying vulnerabilities that could be exploited to compromise data, user accounts, or system functionality. It is one of the most in-demand types of pentesting due to the high level of exposure of applications on the internet.

Key objectives

• Identify vulnerabilities OWASP Top 10 such as SQL injection, XSS, CSRF, insecure access control, sensitive data exposure, and insecure deserialization.
• Evaluate authentication and session management, ensuring there are no flaws that could lead to account hijacking.
• Analyze user input validation to prevent injection attacks or data manipulation.
• Verify security configuration of web servers and frameworks used.
• Verify the security of integrations with APIs and external services.
  

Typical scope

• Corporate applications: client portals, intranets, administration panels.
• E-commerce and payment gateways: online stores and transaction systems.
• Exposed Critical Systems: such as SaaS platforms, CRMs, or ERPs accessible via the internet.
• Hybrid Applications: which combine web frontend and cloud backend.

Mobile Application Pentesting (iOS and Android)

The mobile application pentesting evaluates the security of apps developed for iOS and Android devices, identifying vulnerabilities that could allow data theft, function manipulation, or unauthorized access to backend systems. Given the increasing use of mobile devices in critical transactions and operations, this type of testing is essential to protect both users and the organization.

Main Objectives

• Detect OWASP Mobile Top 10 vulnerabilities, such as insecure data storage, weak authentication, unencrypted communication, or the use of vulnerable libraries.
• Evaluate API security that connect the app with backend systems.
• Analyze business logic to prevent function abuse or control bypasses.
• Verify encryption robustness and credential management.
• Check resistance to reverse engineering techniques and code manipulation.
  

Typical Scope

• Internal Corporate Applications used by employees or partners.
• Commercial Apps on the App Store or Google Play, such as mobile banking, e-commerce, and SaaS services.
• Critical Applications that handle financial, health, or intellectual property data.

DDoS (Distributed Denial of Service) Testing

DDoS testing involves simulating denial-of-service attacks to assess the ability of a network infrastructure, server, or application to withstand a high volume of malicious traffic. The goal is to identify bottlenecks, capacity vulnerabilities, and configurations that could take critical company services offline.

Main Objectives

• Measure the resilience of the infrastructure against unexpected traffic spikes.
• Identify points of failure in the network, load balancers, firewalls, and servers.
• Validate the effectiveness of mitigation systems such as WAFs, CDNs, or scrubbing centers.
• Detect insecure configurations that allow for amplification or protocol abuse.
  

Typical Scope

• Controlled testing in staging environments to avoid impacting live operations.
• Volumetric attack simulation (UDP Flood, ICMP Flood).
• Application layer attack testing (HTTP GET/POST Flood, Slowloris).
• Simulated distributed attacks from multiple geographic locations.

Cloud Infrastructure Pentesting

The cloud infrastructure pentesting assesses the security of environments hosted on platforms like AWS, Microsoft Azure, or Google Cloud Platform. This type of testing aims to identify insecure configurations, excessive permissions, and vulnerabilities in managed services, in order to prevent unauthorized access and data breaches.

Main Objectives

• Detect insecure configurations in cloud compute, storage, network, and database services.
• Evaluate Identity and Access Management (IAM) to identify accounts with excessive permissions or exposed credentials.
• Verify data protection at rest and in transit, by checking for encryption usage.
• Identify vulnerabilities in exposed services publicly or poorly segmented.
• Validate security and compliance policies against applicable regulations and standards.
  

Typical scope

• Production and staging environments in AWS, Azure, GCP, or other providers.
• Critical services such as S3 buckets, EC2 instances, RDS databases, containers, and serverless functions.
• Hybrid integrations between cloud and on-premise data centers.
• Evaluation of multiple regions and accounts to detect security inconsistencies.

Source Code Review (SAST)

A source code review in a pentesting context is a practice that combines security audits with static application analysis (SAST) to identify vulnerabilities directly in the code before the software is deployed to production. This methodology allows for the detection of issues that might go unnoticed in black-box or gray-box testing.

Main objectives

• Identify security vulnerabilities in logic and implementation, such as injections, insecure credential management, or insufficient validations.
• Detect poor coding practices that could lead to exploitable vulnerabilities.
• Evaluate the use of libraries and dependencies to identify vulnerable versions.
• Ensure compliance with secure development standards and applicable regulations.
• Reduce remediation costs by finding issues early in the software development lifecycle.
  

Typical scope

• Web and mobile applications under development or maintenance.
• Backend services and APIs.
• Critical software for operations or that handles sensitive data.
• Specific modules that have changed or require additional validation.

‍

What are the phases of penetration testing?

All penetration tests have different progressive phases or stages. In fact, NIST SP 800-115 states that penetration tests must follow a cycle of planning, discovery, attack, and reporting to ensure their effectiveness and validity.

Cybersecurity specialists must adhere to a protocol to plan and execute each test as effectively as possible. This way, they can verify and ensure the security of the information within the system.

Here, we'll explain each phase in detail and its purpose in organizational systems:

Planning and Scope Definition

In this first stage, the cybersecurity team and the client agree on the objectives, the scope , and the rules of engagement. It is determined which systems, applications, or networks will be evaluated, what techniques are permitted, and within what timeframes the tests will be conducted.

Reconnaissance

This is the phase where the attacker seeks to gather all necessary information about the system or network to be analyzed, in order to successfully carry out the intrusion. It's worth noting that in this phase, the pentesting will not seek to infiltrate the system itself, but rather attempt to gather information from outside. Reconnaissance can be divided into 2 types:

• Passive Reconnaissance: OSINT searches in code repositories, social media, WHOIS records, and breach databases (e.g., HaveIBeenPwned).‍
• Active Reconnaissance: port and service scanning with Nmap, service banner identification, and detection of vulnerable software versions.

Scanning

In this phase, the goal is to actively verify if what was found in the reconnaissance phase shows vulnerabilities that are related to the services discovered. This will help us define the level of difficulty of a potential intrusion.

In fact, this phase of pentesting is of great importance for cybersecurity analysis, as it allows us to verify the security level of the system. Once an overview of the access points is obtained, the system will be accessed through them in the next stage of pentesting.

Exploitation

After finding the vulnerabilities or security gaps that became evident in the previous phase, the goal is now to test them. That is, the personnel responsible for pentesting must attempting to access the system through the detected entry points previously.

Additionally, once they have gained access to the system by exploiting vulnerabilities, the testers will continue to search for potential access points to privileged system levels. The goal is to obtain as much information as possible and demonstrate the damage a cybercriminal could inflict.

The idea is to clearly identify the system's most vulnerable points and what actions can be performed within it, in order to strengthen these weak points and understand their importance in relation to the system's information security. 

Privilege Escalation and Persistence

It is assessed whether an attacker could escalate their privileges and maintain undetected access.

• Vertical Escalation: gaining administrator privileges.
• Horizontal Escalation: accessing data or functions of other users.
• Persistence: creating hidden accounts, installing backdoors, or modifying configurations for future re-entry.

Evidence Removal

After conducting all intrusion tests, it is possible to leave some traces or footprints that could serve as a guide for future attacks.

Therefore, in this phase, any 'trace' that has been left behind must be completely eliminated. If this is not done properly, it would be considered a high-risk vulnerability for the system, completely compromising its cybersecurity.

In this regard, the fact that regularly conduct penetration tests will allow us to keep the system updated and identify new vulnerabilities before others can exploit them for malicious purposes.

Preparation of findings report

The true value of penetration testing lies in the final report. This document details:

• Detected vulnerabilities and exploitation method.
• Evidence (screenshots, logs).
• Risk classification (low, medium, high, critical).
• Concrete recommendations for mitigation and future prevention.

In fact, if you are looking for a penetration testing provider, this is one of the areas where you should pay the most attention when choosing one for your company.

{{body-cta-3}}

At Delta Protect, we are the AI-Powered Security Command Center your Business Needs. With a team of Certified Ethical Hackers, we go beyond traditional penetration tests with our dAttack solution, employing an 80% manual and 20% automated approach to uncover real attack vectors in your infrastructure and help you fix them.

Discover how our service of pentesting, it can be the key component of your security strategy.