Learn the basics of penetration testing—what it is, how it works, and why it’s essential to your organization’s security. Get the facts from Bugcrowd, and arm yourself with proven strategies to stay one step ahead of threat actors.

Penetration Testing Explained

Penetration testing is a methodical process of evaluating the security of a system by attempting to exploit its vulnerabilities and weaknesses. In other words, it’s legal hacking designed to help organizations identify and address potential security risks before threat actors can take advantage of them first.

In this article, we will explore the fundamentals of penetration testing and discuss everything you need to know to get started.

What are the Benefits of Penetration Testing?

Penetration testing offers several benefits:

  • Identifying vulnerabilities: By conducting penetration tests, organizations can identify vulnerabilities and weaknesses in their systems or networks that could be exploited by hackers.
  • Evaluating security controls: Penetration testing allows organizations to evaluate the effectiveness of their existing security controls and identify areas for improvement.
  • Mitigating risks: By addressing vulnerabilities identified during penetration testing, organizations can reduce the risk of potential security breaches and unauthorized access.
  • Compliance requirements: Many industries have regulatory requirements that mandate regular penetration testing to ensure the security of sensitive data.

How Does Penetration Testing Differ from Automated Testing?

Penetration testing and automated testing serve different purposes. While automated testing like scanning focuses on identifying known vulnerabilities and conducting routine checks, penetration testing simulates real-world attacks to identify both known and unknown vulnerabilities. Therefore, penetration testing provides a more comprehensive assessment of a system’s security posture. In some cases, regulatory bodies will mandate penetration tests over automated scanning.


What are the Pros and Cons of Penetration Testing?


Pros of Penetration Testing

Cons of Penetration Testing

Identifying vulnerabilities: Penetration testing helps organizations identify vulnerabilities that can be addressed to enhance their security. Cost: Penetration testing can be expensive, especially for complex systems or large networks. 
Evaluation of security controls: This allows organizations to evaluate the effectiveness of their existing security controls.  Time consuming: It can take time to plan, launch, conduct, and analyze the results of a penetration test. 
Risk mitigation: By addressing vulnerabilities, organizations can reduce the risk of potential security breaches.  Disruption: Penetration testing can cause temporary disruptions to the systems or networks being tested. 

Who Performs Penetration Tests?

Penetration tests are performed by internal teams or external providers, both of which encompass professional pentesters or trusted hackers.

How Much Access Is Given to Pentesters?

The level of access given to pentesters varies depending on the scope of the engagement. Organizations may provide pentesters with limited or full access to simulate a real-world attack scenario. The level of access is also determined by the goals and objectives of the penetration test.

What Are the Types of Penetration Tests?

There are various types of penetration tests:

  • Network Penetration Testing: This type of test focuses on assessing the security of a network to identify potential weaknesses in the network infrastructure and to ensure that effective security measures are in place.
  • Web Application Penetration Testing: This test evaluates the security of web applications by identifying issues such as injection attacks, cross-site scripting (XSS), and insecure configurations. The results help mitigate unauthorized access and data breaches.
  • API Penetration Testing: This test examines the security of application programming interfaces (APIs) by identifying vulnerabilities and potential attack vectors. It ensures that APIs are secure and protected against threats such as unauthorized access, data leakage, and denial-of-service attacks.
  • Cloud Penetration Testing: This test focuses on assessing the security of cloud infrastructure and services by identifying potential vulnerabilities and misconfigurations. Such tests are conducted to ensure that sensitive data stored in the cloud are adequately protected and that access controls are properly implemented.
  • Mobile Penetration Testing: This test evaluates the security of mobile applications by identifying issues that could compromise user data or device functionality. These tests are pivotal in ensuring that mobile apps are secure against various threats, such as data leaks, unauthorized access, and malware.
  • IoT Penetration Testing: This test is conducted to secure Internet of Things (IoT) devices and networks, which often fall prey to unauthorized access and other attacks that compromise the integrity of IoT systems. Such tests help ensure the security and privacy of Internet-connected devices and their users.
  • AI Penetration Testing: This specialized test focuses on the security of AI systems, including the Large Language Models (LLMs) used in conversational AI tools. Aside from identifying potential vulnerabilities, such tests can also be conducted to determine biases in a model’s behavior, ensuring the responsible and secure use of AI technology.

What Happens During a Penetration Test?

A typical penetration test involves the following steps:

  • Planning and reconnaissance: This initial phase involves organizations defining the objectives and scope of the test, including the systems to be assessed and the testing methodologies to be employed. It also entails gathering intelligence and information to enhance pentesters’ understanding of the target’s functioning and potential vulnerabilities.
  • Vulnerability identification: During this stage, the pentester focuses on identifying weaknesses and vulnerabilities within the target system or network.
  • Exploitation: Leveraging the vulnerabilities they have identified, the pentester attempts to exploit them to gain unauthorized access or perform specific actions. This stage involves utilizing web application attacks, such as XSS, SQL injection, and backdoors. Pentesters then strive to escalate privileges, steal data, intercept traffic, and more to assess the potential impact of the identified vulnerabilities.
  • Post-exploitation: If the pentester successfully gains access, they may further explore the compromised system or network to gather additional information or escalate their privileges. The objective is to determine whether any given vulnerability can enable a persistent presence within the exploited system, mimicking advanced persistent threats that often remain undetected for extended periods. The goal of such threats is usually to exfiltrate an organization’s most sensitive data, meaning it is critical that pentesters carry out this step.
  • Reporting: The pentester finally documents their findings and prepares a comprehensive report for an organization, which includes detailed recommendations for enhancing security.

The results of a penetration test typically include:

  1. Specific vulnerabilities that were exploited.
  2. Sensitive data that were accessed.
  3. The duration of undetected access.

What Are the Most Common Penetration Testing Tools?

Penetration testing tools encompass various categories:

  • Open source
  • Web app, network, cloud, wireless, or mobile penetration testing
  • Hardware testing
  • Social engineering

Every tool possesses distinct features and capabilities, making them indispensable elements of any comprehensive penetration testing toolkit.

Open Source Penetration Testing Tools

Nmap: Also known as a network mapper, Nmap analyzes packet responses to map the target network. It helps identify available hosts, services, operating system details, open ports, and potential network vulnerabilities. Nmap is supported by Linux, Windows, and macOS, offering various scan types, from simple port scans to advanced vulnerability scans. It can be used with tools such as Metasploit for automated vulnerability exploitation.

OWASP ZAP: OWASP ZAP is a versatile web app security testing tool. It scans and analyzes responses from target apps, identifying potential vulnerabilities like SQL injection, XSS, and buffer overflow attacks. OWASP ZAP supports passive and active scans, providing an easy-to-use GUI, an intercepting proxy, automated scanners, and plug-ins. Like Nmap, OWASP ZAP works on multiple platforms.

Metasploit: Metasploit offers a comprehensive suite of tools, including an extensive database of exploits and vulnerabilities, for identifying weaknesses in a target system. Its user-friendly interface is ideal for developing and executing exploits, as well as for performing auxiliary tasks like fingerprinting, reconnaissance, and vulnerability scanning. Metasploit seamlessly integrates with other tools and frameworks, such as Nmap and Burp Suite, providing a comprehensive arsenal of penetration testing capabilities.

WPScan: Developed for WordPress, WPScan has a comprehensive database of known vulnerabilities and weaknesses. It can identify usernames, weak passwords, insecure plugin versions, and vulnerable themes. WPScan is a command-line tool with automation capabilities, making it suitable for use in large-scale testing. It is regularly updated to include the latest vulnerabilities.

Web App Penetration Testing Tools

Nikto2: Nikto2 is an open source web server scanner. It excels at identifying outdated software versions, insecure configuration settings, and XSS vulnerabilities.

BurpSuite: BurpSuite is a widely used tool that offers various features, including a proxy server, scanner, intruder, and repeater, making it versatile for comprehensive testing. The proxy server allows users to intercept and modify browser–server traffic, while the scanner automatically detects and exploits vulnerabilities in web applications or APIs. BurpSuite also seamlessly integrates with tools like Metasploit and Nmap, and it comes pre-installed in Kali Linux.

Network Penetration Testing Tools

Wireshark: Wireshark, a popular open source network protocol analyzer, captures and analyzes network traffic across different operating systems. Its real-time packet inspection and filtering features enable focused investigation and enhance analysis efficiency.

Cloud Penetration Testing Tools

ScoutSuite: ScoutSuite is a popular tool used to scan cloud environments for vulnerabilities and misconfigurations. It effortlessly works across AWS, Azure, and GCP in analyzing virtual machines, databases, and storage buckets. It also evaluates compliance with security best practices.

CloudMapper: CloudMapper is an open source cloud security tool that creates detailed visual maps of cloud infrastructure. It identifies security risks and potential attack paths, as well as provides a holistic view of resource relationships. CloudMapper also generates reports with recommendations for addressing vulnerabilities.

Prowler: Prowler is an open source AWS security tool that audits AWS accounts for security best practices. It checks compliance with industry-standard security frameworks like NIST, CIS, and PCI DSS and generates comprehensive audit reports.

Wireless Penetration Testing Tools

Aircrack-ng: Aircrack-ng provides a complete toolkit for monitoring and analyzing network traffic. It is also used to crack passwords to wifi networks that use weak encryption. This open source solution identifies vulnerable access points, monitors network traffic, and tests network security.

Kismet: Kismet offers real-time detection and analysis of wireless network traffic. It provides valuable insights into SSIDs, MAC addresses, signal strength, and more. Pentesters can easily uncover and identify rogue access points, network misconfigurations, and hidden wireless networks with advanced capabilities.

Mobile Penetration Testing Tools

Frida: Frida is a powerful tool for reverse engineering and debugging Android and iOS apps. It enables pentesters to intercept network traffic, manipulate binary code, and alter the behavior of the target app.

Hardware Penetration Testing Tools

Proxmark3: Proxmark3 is an open source hardware tool used in RFID research and testing. It can read and emulate different types of RFID cards and tags, perform wireless analysis, and clone RFID devices. This versatile tool allows pentesters to simulate various attacks, such as replay attacks and man-in-the-middle attacks[.1] , on RFID systems to assess their security.

Social Engineering Penetration Testing Tools

The Social Engineer Toolkit (SET): The Social Engineer Toolkit (SET) is an open source tool that allows users to generate various social engineering attacks, including spear-phishing and credential harvesting. It also provides features for email spoofing, SMS spoofing, and geolocation spoofing. It integrates seamlessly with the Metasploit framework, enabling pentesters to deliver payloads and exploit vulnerabilities effectively.

What Vulnerabilities Can Penetration Tests Uncover?

The findings of a penetration test are unique to each engagement, but recent examples include:

  • CVE-2023-027350: This vulnerability allows remote attackers to bypass authentication on affected installations of PaperCut NG 22.0.5 (Build 63914). Authentication is not required to exploit this vulnerability. The specific flaw exists within the SetupCompleted class. The issue results from improper access control.
  • CVE-2023-34362: A SQL injection vulnerability was found in the MOVEit Transfer web application that could allow an unauthenticated attacker to access MOVEit Transfer’s database. Depending on the database engine being used, an attacker may be able to infer information about the structure and contents of the database and execute SQL statements that alter or delete database elements.
  • CVE-2023-26360: Adobe ColdFusion versions 2018 Update 15 (and earlier) and 2021 Update 5 (and earlier) are affected by an Improper Access Control vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue does not require user interaction. 

What Happens After a Penetration Test?

After a penetration test, the organization receives a detailed report from the pentester. This report includes a summary of the findings, identified vulnerabilities, and recommendations for improving security. The organization can then prioritize and address the identified vulnerabilities to enhance its overall security posture.

TL;DR—Penetration Testing

Penetration testing plays a pivotal role in safeguarding the security of systems and networks. By identifying vulnerabilities and weaknesses, organizations can take proactive measures to reduce the risk of potential security breaches. Regular penetration testing empowers organizations to stay ahead of threat actors and safeguard their valuable data and assets, allowing them not only to protect their brand but also their intellectual property.

Penetration Testing Resources