A Complete Guide to Penetration Testing: Benefits and Best Practices

Here’s a brief scenario of what can happen without penetration testing.

Let’s say you run a financial services company and launch an online portal to streamline loan applications for customers. You trust your skilled development team and choose not to conduct a penetration test before going live.

A malicious actor soon exploits a SQL injection vulnerability in the login form. They bypass authentication mechanisms, access the database you’ve built over the years, and steal over 100,000 customer records. You’re soon under investigation by regulators for a major data privacy violation, and affected customers file a class-action lawsuit. You end up losing a lot of money and customers.

Penetration testing can be a lifesaver for your organization, and this blog post examines the same in detail.

What is Definition of Penetration Testing?

Penetration testing is a type of simulated attack performed by security professionals acting as ethical hackers. They simulate real-world cyberattacks on a network, system, or application to identify vulnerabilities. The test exposes weaknesses cybercriminals might exploit and helps organizations fortify their defenses before they are attacked.

Importance of penetration testing in various sectors

Penetration testing helps different sectors address unique security threats and compliance demands. For example, healthcare organizations can use pen testing to maintain HIPAA compliance and safeguard patient records, while financial institutions can run pen tests to protect sensitive customer data and prevent fraud.

In retail and e-commerce sectors, penetration testing can be used to safeguard customer information and payment systems.

Types of Penetration Testing

There are different types of penetration tests, and they are usually categorized according to their scope, focus, and access level. Here are the main ones:

1. Based on knowledge provided to testers

White box penetration test

Here, ethical hackers have access to full network and system information, including network maps and credentials. They can conduct a thorough examination of internal vulnerabilities by using as many attack vectors as possible to simulate targeted attacks.

Black box penetration test

The pen testers have no information and act like unprivileged attackers, from initial access to exploitation. This penetration test shows how an attacker with no inside knowledge can target and compromise an organization. 

Grey box penetration test

In this penetration test, only limited information is shared with the tester, such as login credentials or partial access. It helps testers know the damage a privileged user with access can cause. A grey box test can simulate an insider threat or one that has breached the network perimeter.

2. Based on the target environment

External network test

This type of penetration testing focuses on vulnerabilities in public-facing infrastructure, such as websites, web servers, DNS, and firewalls. It simulates attacks from outside the network, helping organizations know their security posture against potential external attacks.

Internal network test

A pen tester simulates attacks from within the network, evaluating vulnerabilities that could be exploited by hackers or insiders who have already gained access. The test helps businesses identify vulnerabilities they might miss with external network testing.

Wireless test

Tests an organization's wireless network to identify vulnerabilities in device configurations, access points, and encryption. It’s useful for safeguarding sensitive data and ensuring compliance.

Web application test

This involves performing a simulated attack on a web app to determine weaknesses that hackers can exploit. The tester looks for vulnerabilities like SQL injection, cross-site request forgery, and authentication flaws.

Mobile application test

The ethical hacker simulates real-world attacks to evaluate a mobile application’s resilience to threats such as unauthorized access, data breaches, and insecure storage. Testing helps organizations identify and seal security loopholes before they are exploited by malicious actors.

IoT penetration test

While IoT devices offer many business benefits, they are highly susceptible to cyberattacks. An IoT penetration test finds the security vulnerabilities of IoT devices before they can be exploited.

3. Specialized Types

Red teaming

An ethical hacker simulates an attack by combining multiple testing types to assess a company’s cybersecurity posture and defense readiness. Red teaming helps the company identify vulnerabilities and make targeted improvements.

Social engineering test

This involves assessing how vulnerable an organization's employees are to social engineering attacks. The pen tester conducts different attacks to identify where employees are susceptible and designs a remediation plan. 

Blind penetration testing

The tester is given minimal information, like the company’s URL, and then they try to gain access from that point. The company’s security team is usually aware of the test.

Double-blind penetration testing

The tester and the security team are unaware of the test, as the surprise attack is meant to test detection and response capabilities. The test is useful for assessing how a company would react to an unexpected intrusion.

Client-side penetration testing

Client devices such as workstations and browsers are susceptible to a wide range of cyberattacks, including phishing and malware. A pen test helps assess the risk of cyberattacks. 

Physical penetration testing

What would happen if an attacker gained access to your company’s physical security controls like cameras and locks? This test helps determine how easily an attacker could gain unauthorized access to physical security controls and the damage they could cause once inside.

How does pen testing differ from automated testing? 

Manual pen testing and automated testing have unique strengths and weaknesses. This comparison table highlights the key differences between the two.

Step-by-Step Penetration Testing Process

1. Scoping

Before starting the pen test, take time to define the specific systems, applications, or networks that will be assessed and any limitations or restrictions. This step helps the ethical hackers determine the test’s boundaries and aligns the test with your organization's needs.

2. Reconnaissance

This involves gathering information about the target system or network to understand its strengths and weaknesses. The pen tester collects data from internal and external sources and actively interacts with the target. This helps them to create a profile of the target and plan attack strategies.

3. Penetration attempt

Once familiar with your system, the pen tester will attempt to exploit vulnerabilities. They can escalate privileges, steal data, and intercept traffic to show the damage they can cause. Their goal is to show how far into your environment they can go. 

4. Reporting

In this step, the tester documents and communicates their findings, such as identified vulnerabilities and potential risks. Their report outlines how they infiltrated your system, the security weaknesses they found, and how to remediate them. This is a crucial phase that gives organizations actionable insights on how to improve their security posture.

5. Follow-up

Here, the stakeholders ensure that the recommendations from the report are implemented and that all security loopholes are sealed. The organization also plans to perform regular penetration tests, as this ensures the network, systems, and applications remain secure.

Top Penetration Testing Tools and Platforms

There are many penetration testing tools and services available, each with unique strengths and weaknesses. Here are some of the popular ones:

1. Atlas Systems

Atlas Systems offers comprehensive penetration testing to enhance your company’s cybersecurity posture. Our platform simulates real-world cyberattacks to identify and resolve vulnerabilities in your systems, applications, and network.

2. Kali Linux

This open-source Linux distribution is a popular choice for penetration testing because it has pre-installed tools for security assessments. Cybersecurity professionals use these tools to simulate cyberattacks and identify vulnerabilities.

3. OWASP ZAP (Zed Attack Proxy)

This free, open-source security scanner helps developers find vulnerabilities in web applications during development and testing. It intercepts and scrutinizes HTTP/HTTPS traffic between browsers and web apps to identify potential vulnerabilities, helping testers exploit various security flaws.

4. Nmap (Network Mapper)

This free tool is widely used for network security assessments and investigations. It sends and receives network packets, examines responses, and uses its database and scripting engine to identify active hosts, open ports, and other network vulnerabilities.

5. Nessus

Nessus is a vulnerability scanner that identifies weaknesses in networks and systems by scanning for misconfigurations, vulnerabilities, and compliance issues. It helps testers understand the attack surface by providing detailed reports.

6. Metasploit

This open-source toolkit can research new exploitation techniques, launch attacks, and test defenses. Penetration testers use it to develop and execute exploit code against remote targets. 

Penetration Testing for Third-Party Vendors

A well-structured penetration testing process helps organizations find and address third-party vulnerabilities before attackers can exploit them. Here’s how to go about it. 

1. Planning: Get the vendor’s permission to conduct the test, define the testing approach, and outline the systems, applications, and networks that will be assessed
2. Reconnaissance: Gather information about the vendor’s system or network before you try to exploit it. This includes information like network architecture, domain names, and IP addresses
3. Vulnerability assessment: Use an automated tool and manual techniques to identify known and unknown vulnerabilities 
4. Exploitation: The penetration tester exploits the vulnerabilities to gain unauthorized access to the vendor’s system, application, or network
5. Reporting: The tester writes a report on all findings and gives recommendations for remediation to the vendor
6. Remediation: The primary organization works with the vendor to address the security vulnerabilities

Key Benefits of Regular Pen Testing

Penetration testing is a preventive measure that ensures your company’s network is secure against cyberattacks.

Here are the top benefits of penetration testing:

1. Boosts infrastructure security

A single attack against your company’s infrastructure can disrupt operations and significantly decrease revenue. Pen testing helps identify and resolve weaknesses in your system and network infrastructure before they are exploited by cybercriminals. It maps out potential security gaps before an attack occurs.

2. Ensures compliance

Regulatory standards like PCI DSS require pen testing to show compliance. You can avoid substantial penalties for non-compliance by performing pen tests regularly. Maintaining the required security controls also illustrates your continuous due diligence to regulators.

3. Protects from financial loss

According to Statista, the average cost of a data breach incident is $4.88 million. Losing this much money can send a company to financial ruin. Regular penetration testing doesn’t just protect your business from financial loss; it keeps malicious actors at bay, ensuring your business runs optimally and makes more revenue. 

4. Protects your company’s reputation

You’ve tirelessly worked to make your company what it is today, but a single cyberattack can ruin its reputation, destroying your years of hard work and investment. A damaged reputation can take years to repair and cost you a lot of money. Start scheduling regular penetration tests to avert security breaches and enhance your business reputation.

Best Practices for Effective Penetration Testing

Following the best practices of penetration testing ensures you reap the full benefits. Here are the best practices to follow:

• Scoping is key: Know what you’re testing, why you’re testing it, and how you'll respond to results 
• Hire a skilled tester: Outsource your penetration test if your organization lacks one. They will use their expertise to uncover weaknesses
• Mix automated and manual techniques: The two approaches offer a comprehensive approach to security assessment, helping testers identify a broader range of vulnerabilities
• Follow the law: Get the target’s full consent and authorization before conducting penetration testing. Also, follow all applicable laws and regulations
• Monitor your systems: Monitor your internal systems before and after a pen test to gauge your network's performance and to measure the results 
• Track new developments: Your penetration tests must change as new cyber threats and laws emerge. Ensure penetration testers keep up with new developments to stay ahead of attackers

Strengthen Risk Mitigation with Atlas Systems’ TPRM Tools

Penetration testing is a critical step toward understanding how your organization would fare against a real-world cyberattack. By identifying and validating vulnerabilities before they can be exploited, you gain the insight needed to strengthen defenses and adopt a proactive security strategy.

Atlas Systems goes beyond traditional testing by combining simulated attacks with IT risk assessments, compliance checks, and threat intelligence to provide a comprehensive view of your security posture.

With over 20 years of cybersecurity experience and 100,000+ assessments completed globally, Atlas Systems is a trusted partner for organizations seeking to reduce risk and improve resilience. With tailored remediation strategies, you can stay ahead of evolving threats while ensuring regulatory compliance.

Don’t wait for a breach; strengthen your defenses with Atlas Systems. Get a demo today.

FAQs on Penetration Testing

1. How often should a company conduct penetration testing?

Conducting a penetration test annually is ideal for maintaining a good cybersecurity posture, but regulatory requirements and the company's risk profile also determine testing frequency. Testing is also crucial after a security incident or major changes to business systems.

2. How long does a penetration test usually take?

It can take days or weeks, depending on the scope, complexity, and type of the test. Smaller tests, like web application testing, might take a few days; larger ones, like network security tests, might take weeks.

3. What industries need penetration testing the most?

Industries like healthcare, finance, technology, manufacturing, legal, e-commerce, retail, and critical infrastructure need penetration testing the most because they handle sensitive data, operate critical infrastructure, and must follow strict regulatory requirements. They are frequently targeted by cybercriminals, making penetration testing crucial.

4. Is penetration testing legally required for compliance in any industry?

Yes, penetration testing is a legal requirement for compliance in some industries, like the financial industry. PCI DSS requires annual penetration testing and testing after major changes, while the GLBA, FFIEC, and NYDFS mandate annual penetration testing for protecting customer information.

5. Can penetration testing detect insider threats or only external ones?

Penetration testing is primarily used to identify external threats, but it can also be designed to uncover internal threats. Internal penetration testing identifies vulnerabilities that entities in the network might exploit.