What is penetration testing? A beginner’s guide

Every minute, threat actors launch multiple cyber attacks. While you may think you’re safe with the most sophisticated cyber defenses, these malicious actors often use equally sophisticated tools to breach gaps and launch full-scale attacks. To strengthen cyber security, businesses must implement proactive measures, one of which is penetration testing.

For businesses that handle sensitive data, such as those in the financial industry, penetration testing is required by several information security and regulatory compliance frameworks. For instance, both the PCI DSS and FTC Safeguards Rule explicitly mandate organizations to conduct penetration testing at least once a year.

In this guide, we help you understand what penetration testing is and its importance in safeguarding your systems. We explain how the process works and how you can easily implement it to augment your cyber security strategies.

What is penetration testing?

Penetration testing, or pen testing, is a cyber security practice where security experts simulate real-world attacks to check how strong defenses are. These experts try to break into network security through weaknesses or gaps not previously identified. If they can get in, changes must be made to bolster security.

Simply put, pen testing allows security professionals to try to hack into your systems to identify vulnerabilities, assess risks, and enhance security. This fake cyber attack is also why pen testing is often referred to as ethical hacking.

Isn’t this the same as a vulnerability assessment? No.

Vulnerability assessments are like a health check. It scans for weaknesses and prioritizes which ones need urgent attention. However, it doesn’t test if and how those weaknesses can actually be exploited.

Penetration testing steps in at this point and uncovers how dangerous those weaknesses can be. Simulating cyber attacks can reveal how real hackers might exploit the weaknesses and the extent of damage they might cause once those gaps are breached.

While both penetration testing and vulnerability assessments help find security problems, they are distinct processes that serve different purposes in cyber security. Keep in mind that both are integral to any cyber security strategy.

Why is penetration testing important?

In the Global Cybersecurity Outlook 2025, 72% of business leaders reported an increase in cyber risks. A further increase is anticipated as both organizational and personal attack surfaces expand due to geopolitical tensions, complex supply chains, and the rapid adoption of emerging technologies. GenAI, in particular, is powering identity theft, phishing, and social engineering attacks.

Without proactive security measures, your organization can fall victim to ransomware, cyber-enabled fraud, supply chain disruptions, and other attacks. You may also unwittingly violate data privacy regulations and face legal and financial consequences. Suffice it to say that boosting your cyber defenses is important to keep all fronts covered and avoid financial, reputational, and legal repercussions.

Penetration testing helps augment your defenses by reducing risks, ensuring compliance with industry standards, and maintaining user trust. Pen testing enables you to:

• Find security gaps that make your systems vulnerable to threats
• Fix security issues before hackers find and exploit them
• Protect customers and enterprise data from being breached, compromised, or leaked
• Maintain compliance with laws that require companies to test security regularly

By finding and fixing security problems early, penetration testing makes the digital world safer for everyone.

In the Paris Olympic games, for instance, penetration testing was among the key strategies in cyber securing the event. According to the WEF report on cyber security, the National Cybersecurity Agency of France implemented large-scale audits, penetration testing, and cyber-crisis management exercises to prepare for potential cyber attacks during the Games. Due to their proactive measures, there were no disruptions during the event, and the infrastructure was not affected despite the significant number of attempted cyber attacks.

Types of penetration testing

Now that it’s clear how important penetration testing is today, let’s explore the different types of penetration testing and which issues they address.

1. External Testing

This test looks at anything a hacker might see from the outside. Websites, firewalls, servers, and other external-facing assets are checked to see if someone from outside the company can break into them. The pen tester usually conducts this test from a remote location or somewhere outside the premises. Basically, it checks if your exterior walls are impenetrable. If they’re not, you can repair or reinforce weaknesses before threat actors find them.

2. Internal Testing

Not all attacks are done by external threat actors. Threats can also come from inside the organization, such as from a disgruntled employee or a hacker who might have gotten inside the premises. Threats may also arise if someone misuses their access privileges or inadvertently discloses confidential information. According to Statista, 70% of sensitive data loss is caused by careless users and 20% by malicious employees or contractors.

Internal pen testing searches for loopholes within the organization’s network and systems. This prevents both intentional and accidental data leaks that could compromise sensitive data.

3. Web Application Testing

Most businesses today use web applications like shopping sites and mobile apps. Since these apps are used by the public, they are even more susceptible to hacking. For example, a threat actor might use SQL injection to bypass security checks in log-in forms. Even a seemingly small mistake in a website’s security can expose thousands of users to danger.  

To avoid this, pen testers look for weak spots in web apps that can be exploited to steal customer data or take over the system.

4. Social Engineering

People make mistakes, and threat actors take advantage of this. Employees or web users can be tricked into giving away sensitive information that hackers can use to gain access to an organization’s network.

Pen testers minimize the risks of social engineering attacks by raising awareness among employees and other internal users. They may send fake emails to simulate phishing attacks or make phone calls pretending to be from IT support. These tests focus on the human element of cyber security and point out the need for heightened security training when necessary.

5. Wireless Testing

Weak passwords or outdated security settings on wireless networks and devices make it easy for malicious hackers to break in. They can sit somewhere near the building and try to access the company’s Wi-Fi. With penetration testing, organizations can make sure that their wireless security is strong so that no unauthorized people can connect and steal information.

Cyber threat actors attack organizations in multiple ways. As such, the different types of penetration testing are all equally important for your cyber security strategy.

The penetration testing process

The process for penetration testing can differ for each organization and situation. Although there may be slight differences in how the process is implemented, these core steps typically include:

1. Planning

The first step in penetration testing is defining the scope, objectives, and legal permissions. Decision makers and penetration testers discuss what areas must be tested, what the goals are, and how to go about the test. This, essentially, is your game plan.

• Scope: Which part of the network will be tested? What type of penetration tests would be used?
• Objectives: Are you trying to find weak points only? Are you looking for a specific type of attack?
• Legal permissions: Does the ethical hacker have permission from the organization? Are protocols in place to ensure that privacy is not violated, and no laws are broken?

2. Reconnaissance

Once the plan is in place and all permissions are acquired, penetration testers can now start with information gathering. They try to learn as much as they can about the target systems, including all information about the company that is known to the public. They also try to find out as much as they can about how the company network is set up and what technologies it uses.

At this point, penetration testers use advanced tools to scan your network for weaknesses. They’ll look for old software versions or bad configurations that they can use to get into your systems.

3. Exploitation

Armed with knowledge about your network and its weaknesses, penetration testers can now simulate attacks. They will do all they can to try and exploit the weaknesses they found during their reconnaissance. They might try to break into a website, access sensitive data, or take control of a system. The goal is to see if and how a hacker could attack the system using the vulnerabilities they discovered.

4. Analysis

After the test, the penetration testers document their findings. They put everything they did during the test on record, including the weaknesses they found, how they breached gaps, and what information they gained access to.

With these details, they can evaluate the potential impact of an actual breach. They assess how serious each weakness is, and which ones need to be fixed first.

5. Reporting

To help you make well-informed decisions on your cyber security strategy, the penetration testers provide a detailed report that includes vulnerabilities found and suggestions for fixing them. These actionable recommendations for remediation can guide you on what to do next to protect your network from actual attacks.

Common challenges and tips for success

Penetration testing is a complex task. Organizations that implement it often face difficulties. Here are some of the common challenges and tips on how to overcome them.

• Ethical and legal considerations. Because pen testing simulates real attacks, testers can potentially access enterprise data and cause disruption during the test. So, it is important for testers to get clear permission and a defined scope for the test. They must make sure that the test does not harm anyone, violate privacy, disrupt systems, or break any rules.
• Complex systems. Many organizations use complicated technology systems with multiple layers of security. It can be tough to test everything thoroughly and find all the weak spots. Instead of testing everything all at once, break down and prioritize your system. Use a risk-based approach to focus on the most critical areas first, such as databases, log-in systems, and external-facing applications, where a breach could cause the most damage.
• Limited resources. Some organizations have lean IT teams and may not have the right talent and skills to do thorough penetration testing. To avoid gaps in security, augment your IT team with security experts from reliable companies like Claro Enterprise Solutions.
• Emerging threats. Cyber threat actors are always finding new ways to breach systems. Ransomware-as-a-service, cyber-enabled fraud, GenAI-powered social engineering, and other sophisticated attacks pose constant cyber risks. To keep your network safe from these relentless threats, you must conduct regular vulnerability assessments and penetration testing.

The Future of penetration testing

Almost half of the Global Cybersecurity Outlook 2025 respondents cited cyber attacks augmented by generative AI as their primary concern this year. Phishing and social engineering attacks are becoming more sophisticated and widespread. Supply chains are also becoming increasingly complex, opening organizations to attacks within the ecosystem.

As cyber threat actors use smarter techniques and new technologies emerge, penetration testers must stay ahead by learning new skills, keeping up with trends, and adapting to changing threats.  

Despite the growing cyber threats, many organizations are not fully prepared to handle them. In fact, two in three organizations are currently faced with a moderate to critical shortage of cyber talent, reflecting an 8% increase in cyber skills gaps since last year.

If your organization is among those lacking robust cyber teams, getting help from cyber security experts like Claro Enterprise Solutions can give you access to essential tools, expertise, and strategies you need to stay ahead of evolving threats.

How to be proactive with penetration testing

AI-driven threats and the cyber security skills gap make it more important than ever to take action. One proactive step to strengthen cyber security is regular penetration testing. By identifying and fixing weaknesses before attackers exploit them, you can reduce risks and avoid costly breaches.

In reading this guide, you have already taken the first step toward learning and applying penetration testing techniques. Because threats continue to evolve, it is important for you to stay up to date with the latest cybersecurity solutions.  

Explore more of our resources on penetration testing or  meet with one of our expertsmeet with one of our experts.

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