Penetration testing explained: Benefits, types, and methods

What is penetration testing in cybersecurity?

Penetration testing, also known as pen testing or pentesting, is an authorized benign attack against a computer system or network. A type of ethical hacking, pen testing helps uncover vulnerabilities that hackers might exploit in real-world attacks.

White hat hackers can use penetration testing techniques on all or different network parts, including application protocol interfaces (APIs) or frontend and backend servers. Pentesting is also useful for testing the web application firewall (WAF) and practically any other IT component within the system that could be targeted for hacking.

Vulnerability scanning vs. penetration testing

The main difference between vulnerability scanning and penetration testing is that while vulnerability testing points to the weaknesses within the network or device’s operating system, penetration testing also includes exploiting these vulnerabilities.

Vulnerability assessment can help to identify known weaknesses across a range of different systems. Meanwhile, pen testing is a much more targeted process that relies on manual system testing in most cases. It focuses more on assessing the possible consequences of a system breach rather than simply detecting vulnerabilities.

Why is penetration testing so important?

The primary goal of penetration testing is to identify unknown security issues and reveal the targeted system’s defensive strength. It’s an essential part of any comprehensive risk assessment in many big and small enterprises. The information gathered from these ethical attacks is used to patch security loopholes and improve overall network security before attackers take advantage of them.

In addition to improving security, some companies use pen testing for security audits. Sometimes, companies can gain particular security standards only by doing a certified penetration test.

Who performs penetration testing

External companies that offer penetration test services usually undertake pen testing requests. Outsiders with little to no knowledge about the target are more likely to spot vulnerabilities compared to developers who created the website or app.

The contractors are usually referred to as ethical hackers. Most of them are experienced cybersecurity professionals specializing in pen testing and have degrees in this field. However, some are self-taught and might even be reformed criminal hackers who have decided to use their skills for good. You can read more about different types of hackers in this post.

Penetration testing steps

A pen test is usually accomplished in five steps — learn more about the pentesting process below.

1. 1.Planning and reconnaissance. During this stage, the ethical hacker and the company decide on the scope, the goals, the methods, and the systems that will be tested. The pentester gathers information about the network and identifies potential vulnerabilities.
2. 2.Scanning. During the scanning stage, the pen tester identifies how the target network or application responds to intrusion attempts. This step is usually done using static analysis, which scans the application’s code without executing it, and dynamic analysis, which checks the code in its running state. Scanning provides real-time data on application performance.
3. 3.Gaining access. Now the tester has enough information to try to exploit vulnerabilities. Their goal is to get into the system, steal sensitive data, disrupt the service, or get admin access and escalate their privileges. They can achieve this by using any attack, such as cross-site scripting, SQL injection, brute-force attacks, and social engineering attacks.
4. 4.Maintaining access. Once the hacker is in the system, their job is to stay there for as long as they can or extract the most sensitive data they can find. As part of the attack, the hacker could also cover their tracks to stay as disguised as possible by clearing any gathered data and logs.
5. 5.Analysis. The last step is to compile all this information – the vulnerabilities, how they were exploited, and how long the hacker stayed in the system – and present them all in a report. Security professionals then analyze the report, and the company takes the appropriate actions to patch the found vulnerabilities and improve security controls. The upgrades can include new WAF rules, DDoS mitigation, tighter validations, or new staff training on better recognizing phishing attacks.

Penetration testing methodologies

Ethical hackers use different types of pen testing techniques to achieve different goals. The most popular pentesting methodologies include:

• White-box testing. Before this test, the pen tester receives detailed information about their target. This information often includes IP addresses, network infrastructure schemes, protocols, and source code.
• External or black-box testing. This type of testing targets the company’s assets that are only visible externally. An example of an external test could be website penetration testing, targeting web applications, email, or DNS servers. During the attack, the tester is not allowed into the building, where they can access the company’s servers or employees' computers – they need to perform the attack from a remote location or nearby buildings.
• Internal testing searches for vulnerabilities behind the firewall, in other words, what a hacker could exploit once they are inside the system. That doesn’t mean they only test what a malicious employee could do. A hacker could use social engineering techniques, such as phishing links, to gain insider access.
• During blind testing, the hacker is given limited information about the company, usually only its name. This helps to see how the attack would happen in a real-life situation.
• Double-blind testing. The idea behind this type of attack is that the security personnel responding to it aren’t notified about the attack, so they cannot prepare for it any sooner than they would in a real-life scenario. It’s particularly useful for testing a company’s security monitoring, incident identification, and response procedures.
• During targeted testing, the penetration tester and the security team communicate with each other at every single step of the attack. The attacker gives the security professionals their feedback, which works as a great defense training exercise.

Types of penetration testing

Pen testing was designed for targeted attacks, allowing enterprises to decide which elements of their IT infrastructure they want to test for vulnerabilities. These elements are the main factors that determine the penetration testing type. The most popular penetration testing types include these IT infrastructure segments:

• Network. Whenever pen testers check a network’s strength, they look deeper into its hardware and software components, configurations, and operational weaknesses. Security experts often map the network, scan its ports, analyze data packets, and execute exploit codes.
• Web application. Penetration testing for web applications is crucial because they are publicly available and widely used, making them one of the primary targets for malicious actors. To check a web app’s resilience, ethical hackers try to intercept traffic, exploit SQL injection flaws, and search for outdated server software.
• Wireless. Otherwise known as Wi-Fi pentesting, the security testing for wireless networks includes checking the effectiveness of its encryption mechanisms, access controls, and privacy settings. Among the tools used for this type of testing are password cracking, analysis of captured packets, and WPS vulnerability exploitation.
• Social engineering. Penetration testers may also use various techniques to trick enterprise employees into giving away their credentials or letting attackers into the network. This is usually done through phishing emails and messages with attached malicious links or files.
• Physical. This type of penetration testing concerns the enterprise’s physical barriers and procedures, simulating attacks on the company’s locks, alarms, cameras, and access control systems. Pen testers often employ various lock-picking tools, badge cloning devices to replicate access cards, and surveillance equipment to find the black spots of the cameras.
• Mobile application. Whenever penetration testers aim to find vulnerabilities within mobile applications, they try to compromise user data and impair app functionality and mobile operating systems. To do that, they use static analysis, runtime manipulation, and network traffic sniffing and analysis.
• Cloud. Compromising cloud infrastructure can lead to data breaches and open a way for unauthorized access to critical resources. Ethical hackers often search for vulnerabilities within cloud-based systems by identifying misconfigurations and manually testing possible attack scenarios that automated tools might miss.

What are the benefits of pen testing?

Penetration testing is a powerful tool that brings a new perspective to enhancing companies' security. Overall, pentesting tools are beneficial for:

• Mitigating security risks. Pentesting allows enterprises to mend security gaps before hackers can find and exploit them. Resolving security issues before they cause real trouble helps to lower the risk of data breaches and avoid financial losses.
• Improving the company’s security level. Companies can strengthen their defenses against cybercrimes by continuously patching possible vulnerabilities and enhancing their security posture.
• Complying with industry standards better. It’s not only the tech industry that has high security standards. Many enterprises use penetration testing techniques to keep their security systems in an optimal state to meet their industry standards.
• Making more cost-effective security investments. Penetration testing enables companies to identify critical vulnerabilities in time, preventing them from data breaches and legal liabilities that may follow. This allows for saving significant costs related to security incident remediation.