Pentest: What is it? How does it work?

Pentesting enables the effective identification of security vulnerabilities within computer systems before they can be exploited by hackers. Learn how this strategy safeguards businesses by testing their defenses in a manner akin to that of a real hacker.

What is a pentest?

Definition of Pentest

A penetration test, commonly referred to as a pentest, is a security audit that simulates a cyberattack. In this process, the pentester, acting as an ethical hacker, attempts to infiltrate an organization’s computer system. This can occur through multiple entry points such as networks, websites, applications, user accounts, or connected devices.

The aim is to identify API security vulnerabilities before real cybercriminals find them. For this purpose, the pentester employs various testing methods, including social engineering, to detect all potential vulnerabilities. Upon identifying weaknesses, they prepare detailed pentest reports and recommend strategies to enhance system security.

It’s a “preventive cyberattack” approach that facilitates the evaluation and reinforcement of sensitive data protection. This practice, which adheres to modern security standards, has become crucial for any organization focused on its cybersecurity.

It’s similar to a “preventive cyberattack” or an “offensive evaluation,” with the goal being to assess the robustness of IT systems.

What are the benefits of pentesting?

1. Countering the evolution of threats: As cyberattacks grow more sophisticated, penetration tests become increasingly vital. To thwart attacks, businesses must fortify themselves, which necessitates constant monitoring and frequent pentests. They are essential for identifying security vulnerabilities, mitigating them, and thereby bolstering the information system’s protection.
2. Enhancing the security of web applications: Although engaging a pentester is a considerable investment, it is crucial for proactively identifying security vulnerabilities before cybercriminals can exploit them.
3. Preventing massive financial losses: During cyberattacks, companies might lose millions or even billions due to business disruptions, ransom demands, not to mention the damage to their brand reputation. This is why cybersecurity professionals are in high demand across all industries.
4. Regulatory compliance: A pentest is also essential for meeting regulatory requirements. For instance, the GDPR mandates that companies secure their information systems to prevent data breaches. Organizations seeking certification (like ISO 27001) must perform penetration testing as a sine qua non condition for approval.

Vulnerability scan or pentest?

Criteria	Vulnerability scan	Pentest
Type	Automated analysis	In-depth manual analysis
Objective	Quick detection of vulnerabilities	Simulation of a real attack
Depth	Superficial	Detailed, targeting complex vulnerabilities
Cost	Affordable	Higher
Frequency	Regular	Periodic (audit)
Expertise	Basic technical	Cybersecurity expert required

Vulnerability scans and pentests are two complementary approaches in cybersecurity. Scans provide rapid and regular identification of prevalent vulnerabilities using automated tools, vital for the ongoing maintenance of a system’s security.

Conversely, a pentest offers a more advanced approach. By mimicking a genuine attack, it enables the examination of vulnerability exploitation and assesses the overall system resilience. It’s the perfect method for comprehensive audits, revealing complex vulnerabilities that automated tools often miss.

By integrating these methods, companies achieve a complete security perspective: consistent monitoring through scanning, paired with in-depth analysis and strategic advice from pentesting.

What are the different types of penetration tests?

Given the complexity of information systems, pentests can target various areas. Accordingly, they are categorized into several types. Here are the most prevalent:

• Internal network penetration test: It evaluates servers, network equipment, workstations, Wi-Fi, Active Directory, etc., to assess security from an insider attacker’s perspective.
• Web application penetration test: It seeks vulnerabilities related to the infrastructure configurations hosting the services (servers, cloud environments).
• Mobile application penetration test: It includes a static analysis and a dynamic analysis of the application. Static analysis extracts components for reverse engineering attempts, while dynamic analysis identifies vulnerabilities during app execution.
• API penetration test: It can be performed independently or as part of a web or mobile application pentest. This interface has specific vulnerabilities, like broken authentication, unchecked resource consumption, server-side request forgery, etc.
• IoT and connected devices penetration tests: All layers of the IoT ecosystem are analyzed, including hardware, firmware, communication protocols, servers, web applications, and mobile applications.

3 pentesting methodologies

Prior to delving into the steps of pentesting, it’s important to note that penetration tests can be undertaken using three different approaches:

• Blackbox pentest: the pentester doesn’t have access to the information system’s data. They approach the system as an outsider to the organization.
• Greybox pentest: the pentester has access to some information but not all. For instance, certain user accounts.
• Whitebox pentest: the pentester has full access to all the available data, including the source code and the system administrator account of the information systems.

By employing these different methodologies, one can prepare for all kinds of attacks.

The 8 steps of penetration testing

To conduct a pentest, the cyber expert must adhere to a detailed plan consisting of 8 steps:

• Target reconnaissance: this step involves gathering data about the nature of the test (network, API, application, …) and the specified target.
• Mapping: this is the process of creating a map of the information system. Its purpose is to list assets.
• Vulnerability research: this is when the pentester examines the IS for weaknesses.
• Exploitation: the pentester utilizes the identified vulnerabilities to assess their severity.
• Privilege escalation: the pentester assumes the role of a hacker, temporarily acquiring administrator rights (the privileges) to execute their attacks.
• Propagation: this involves determining the extent of the vulnerability. To do this, the pentester expands their attack to other devices within the IT infrastructure.
• Cleaning: the system is cleansed and reverted to its original state.
• Reporting: the pentester documents all the actions performed during the penetration test and offers recommendations for remedying the deficiencies.

Throughout these stages, the pentester utilizes a variety of tools, such as Burp Suite, Kali Linux, Metasploit, Hashcat, Nmap, Ettercap, SQLmap, etc.

How to perform a pentest?

3 pentesting methodologies

Penetration tests can be conducted in three varied ways:

• Blackbox pentest: The pentester has no access to the information system’s data, mimicking an external attacker.
• Greybox pentest: The pentester has limited information, such as some user accounts.
• Whitebox pentest: The pentester has complete data access, including source code and administrator accounts information.

Combining these methods helps cover a wide range of threat scenarios. For instance, a blackbox test assesses external defenses’ strength, while a whitebox test uncovers complex internal vulnerabilities, often due to misconfigurations or insecure IDE development practices. This hybrid method is commonly preferred for a comprehensive security assessment.

The 8 stages of penetration testing

To execute a pentest, a cybersecurity expert follows a specific process:

• Target reconnaissance: Gather data relevant to the test type (network, API, application, etc.) and the selected target.
• Mapping: This step involves mapping the information system and inventorying assets.
• Vulnerability research: The pentester examines the system’s weaknesses.
• Exploitation: The pentester exploits identified vulnerabilities and evaluates their criticality.
• Privilege escalation: The pentester acts as a cybercriminal, temporarily gaining system administrator rights to carry out additional attacks.
• Propagation: The pentester understands a vulnerability’s scope by extending the attack to other devices.
• Cleanup: The system is restored to its original state.
• Report: The pentester documents all actions taken during testing and offers recommendations for remediation.

What are the tools of pentesting?

Tools	Functionality		Examples
Static analysis	Automatically detects vulnerabilities in source code.		SonarLint, Checkmarx, Snyk
Dependency management	Analyzes external libraries for vulnerabilities.		OWASP Dependency-Check, Dependabot
Linting	Enforces secure coding practices.		ESLint, Pylint, StyleCop
Secret detection	Finds exposed API keys or passwords in the code.		GitGuardian, TruffleHog
Proxy and dynamic tests	Tests the application’s behavior in real-time.		OWASP ZAP, Burp Suite CLI
Automated tests	Executes security tests in CI/CD pipelines.		ZAP CLI, GitLab CI/CD, Jenkins
Version control	Protects against leaks of sensitive information in Git.		GitGuardian, Git Hooks

Incorporating these tools within IDEs helps enforce security from the development phase, thus mitigating vulnerabilities in production. A combination of static analyses, dependency management, and dynamic tests ensures sustained security throughout the development lifecycle.

Conclusion

Pentesting has evolved into a fundamental component of cybersecurity. Organizations actively pursue professionals who can detect and thwart threats before they inflict harm.

Training in pentesting extends beyond advanced technical skills to include strategic thinking, essential for comprehending attacker methods. It’s a field that blends analysis, investigation, and creativity, confronting ever-changing challenges.