Your Guide to Simulated Cyberattacks: What is Penetration Testing?

Penetration testing simulates a real-world cyber-attack on your critical data and systems. Here’s what penetration testing is, the processes and tools behind it, and how pen testing helps spot vulnerabilities before hackers do.
David Harrington
7 min read
Last updated June 12, 2023

Without penetration testing, you might not recognize gaps, weaknesses, and vulnerabilities in your cyber defenses until it’s too late. A penetration test is essentially a simulation cyber-attack, where an internal team or partner will act as a hacker in an attempt to penetration your systems, data, or networks.

Penetration testing has quickly become a standard operating procedure for information and data security teams across most industries and in both private and public sectors. If regular penetration testing isn’t currently a part of your cyber defense regime, now is the time to get informed and start planning.

Here we’ll provide you with an overview of pen testing, how it works, and what the process typically looks like. We’ll also help you decide what kind of methodology is right for your organization and penetration testing tools that are potentially at your disposal.

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What is Penetration Testing?

A penetration test, or pen test for short, is a cyber-attack simulation designed to discover and check for potential vulnerabilities before real-life hackers can take advantage of them. Penetration testing may involve attempting to breach any number of endpoints or applications, from application protocol interfaces (APIs) to backend servers.

Pen testing falls under the category of what is called Ethical Attacks, where no actual harm is done and the hack is for the benefit of organizational cybersecurity. For instance, a malware penetration test might begin with a phishing attack against an unsuspecting employee, but with no malicious code released should the individual click a link or download the file.

After a pen test is complete, infosec and executive teams will review the results and formulate a game plan to improve cyber defense posture and remediate weaknesses based on any successful efforts of the simulated hack.

Elements of Pen Testing

No matter what type of penetration testing you choose, similar parties and elements will typically be involved. Here are the core elements of pen testing, who’s involved, and what they’re responsible for:

  • Red Team. This is the team of ethical hackers who will be conducting the attack simulation. The Red Team can either be an internal team of experts, someone you hire to assist with the pen test or a mix of both. 
  • Blue Team. This is the internal cybersecurity team that the hackers are testing. The Blue Team usually consists of whatever cybersecurity personnel or measures that were previously in place, putting their effectiveness and performance to the test.
  • Executive Team. Most organizations involve the executive level in penetration testing, whether it be the CEO, CTO, or CIO. While the C-Level may not be directly involved in the actual pen test, they will likely be involved in planning, reporting, and assessment.
  • Testing Partner. It’s common for companies to outsource the ethical hack or part of the Red Team activities to ensure a comprehensive penetration test. If your internal team lacks certain pen-testing tools or capabilities, a partner may be appropriate.

Pen testing can involve other parties, but these are the main groups you’ll need to include. 

Benefits of Penetration Testing

Penetration testing is primarily designed to exploit potential weaknesses before real hackers do, and there are multiple benefits to conducting ethical hacks on a regular basis. Here are some of the core reasons to conduct security penetration testing

  • Vulnerability Identification. Penetration first and foremost will help you identify vulnerabilities that would otherwise remain hidden.
  • Cyber Defense Testing. You’ll also get a sense of your organization-wide cyber defense capacity, threat alert capabilities, and response times.
  • Firewall Assessment. More specifically, you’ll see how effective your current firewall software and configurations are against potential attacks.
  • New Threat Discovery. Pen testing partners will often employ the newest hacker tactics, letting you know if your defenses are effective against innovative threats.
  • Regulatory Compliance. Penetration testing typically helps your cyber defenses become compliant, whether it’s HIPAA, PCI-DSS, or other relevant frameworks.
  • Downtime Minimization. When an attack does occur, pen-testing ensures that your Blue Teams know exactly how to respond and get things back online in short order.
  • Risk Prioritization. After conducting a pen test, you’ll have a better idea of the risks to your data and systems and how to prioritize your resources in mitigating those risks.
  • Customer Trust. Conducting an annual penetration test is something you can communicate to your clients and customers to enhance trust in doing business with you.

There are other ancillary benefits to penetration that are more downstream in the value chain, but these are some of the main reasons why regular penetration testing is critical to any business. 

Methods of Penetration Testing

Now that you know what pen testing is and why you should conduct them, let’s get into the specific types and methods of penetration testing.

Internal Pen Test

In this variety of network penetration testing, the attackers perform the test from within an organization’s internal network. This type of pen test is particularly useful in determining the extent to which insider threats can cause harm. Whether it’s a disgruntled employee or an unsuspecting phishing victim, internal pen tests are both extremely useful, common and should be a part of your regular testing routine.

External Pen Test

Another important method of pen testing, external tests simulate an attack from the outside on things like your servers, networks, and firewalls. External pen tests are designed to put your cyber defense measures to the test. The Red Team will typically conduct the attack from a remote location outside your office building from another office or mobile van parked nearby. External tests usually target things like servers or web applications for the purposes of data extraction or disabling systems for a ransomware attack.

Covert Pen Test

Otherwise called a Double-Blind pen test, in this situation virtually nobody in the company is aware that the pen test is taking place. This includes the IT and infosec professionals tasked with the response. Covert pen tests can be organized by the executive or corporate levels to gain the most accurate picture of cyber defense effectiveness. But it’s also important to designate the scope and have a written agreement with the ethical hacker ahead of time to avoid any potential issues with law enforcement. 

Targeted Pen Test

In this instance, both the attackers and internal security personnel collaborate throughout the process, keeping one other appraised of their movements. Targeted testing is a valuable methodology that gives security teams real-time feedback from a would-be hacker’s point of view. Organizations can also focus on certain aspects of cyber defenses, such as firewalls or cloud security, during these types of pen tests. As ethical hackers and internal staff communicate throughout the hack, specific aspects of cybersecurity can be fine-tuned more effectively than in a general internal or external test.

Penetration Testing Stages

In general, the pen testing process can be broken down into the following five stages:

1. Planning & Reconnaissance

First off, you’ll want to define the scope and goals of your pen test. What systems do you plan on testing? Are there certain vulnerabilities you’re looking to address? And when methods do you expect to use? Gather all the intelligence you need about what you’ll target and scout out the landscape so that your ethical hackers can do their job most effectively.

2. Scanning 

Next, you need to understand how your target systems and applications will likely react to various hacking attempts. Using static analysis scanning, you can inspect an application’s code in a single pass and estimate how it behaves while it’s running. You can also conduct dynamic scanning, which provides a more real-time view of an application's performance and is also more practical than static analysis.

3. Gaining Access

Here is where the actual attack simulation begins. The Red Team will conduct a web application, social engineering, or other types of attacks to gain entry into your systems. Tactics like SQL injections and phishing will typically be employed. The Red Team will continue trying a variety of measures to escalate privileges, steal data, intercept traffic, or any other number of activities that can open the door for potential damage.

4. Maintaining Access

One inside, the next goal for the ethical hackers will be to achieve a persistent presence in the exploited system. Like a real hacker, they’ll want to gain access long enough to achieve their objectives, whether it’s data theft, malware injection, or disabling systems. This serves to mimic advanced persistent threats that can remain in a system for days, weeks or even months to compromise an organization’s critical data and systems.

5. Analysis

Once the actual penetration test is complete, the results are compiled into a detailed report for analysis by executives, infosec teams, and any other relevant personnel. Their analysis will typically include the specific vulnerabilities exploited, what sensitive data (if any) were accessed, and how critical systems were affected. Post pentest analysis will also look at how long hackers were able to remain in -- and move about -- systems undetected. 

And once the analysis is complete, a remediation plan will then be formulated and put into action based on the discovered and exploited vulnerabilities. Organizations may take steps like re-configuring firewall settings or implementing a data-centric threat detection solution to address the gaps.

Types of Pen Testing

To ensure that your pen tests achieve the right objectives and pinpoint weaknesses, consider these various different types of pen tests that focus on different areas of an IT infrastructure:

Web Application Pen Test

This type of test examines the overall security and potential risks of your web applications. This includes things like injection vulnerabilities, broken authentication or authorization, and coding errors.

Network Security Test

This type of test focuses on network security by exploiting and uncovering vulnerabilities on different types of networks and associated devices. The goal is to exploit flaws like weak passwords or misconfigured assets, allowing Red Team access to critical systems or data.

Social Engineering Test

Social engineering involves using deception to gain access or information for malicious purposes. Phishing is the most common type of social engineering pen test, where ethical hackers will test the awareness of personnel and employees with scam-like emails.

Cloud Security Test

Here, security teams will work with third-party vendors and cloud providers to execute a cloud-specific attack simulation. Cloud pen tests validate the security of your cloud deployment and identify the overall risk and likelihood for each vulnerability detected.

Penetration Testing Tools

There are a plethora of electronic penetration testing tools on the market that are widely available. An experienced pen-testing partner can help you choose the right stack for your specific organization, but here are a few of the best to consider:

  • Powershell-suite. A collection of PowerShell scripts that extract information about the handles, processes, DLLs, and many other aspects of Windows machines. Powershell-suite easily automates tasks to discover exploitable assets on any network. 
  • Wireshark. The most widely used network protocol analyzer across the world. Network traffic captured via Wireshark shows which protocols and systems are live and is best for deep-level visibility into network communications.
  • Metasploit. Originally an open-source solution, Metasploit can help with vulnerability scanning, listening, exploiting known vulnerabilities, evidence collection, and project reporting. Best for managing multiple pen tests or applications at once.
  • MobSF. The best tool for discovering mobile platform vulnerabilities. Also comes with built-in REST APIs for integrating pen-testing into your development pipeline. Conducts both static and dynamic mobile application analysis.
  • Apktool. A tool for reverse engineering malware for pen testers to use during exercises. Apktool can mimic and simulate malware payload delivery to determine whether an organization’s cyber defenses can ward off the specific malicious code.

These tools cover most of the key pen-testing areas like scanning, analysis, and vulnerability testing. For a more comprehensive list, check out this list of recommended penetration testing tools.

Pen Testing FAQs

Who performs penetration tests?

Both internal company staff and external partners. Penetration test attack simulations are conducted by what’s called Red Teams, ethical hackers tasked with hacking into systems. Defense personnel, or Blue Teams, defend against the attack like they would in real life.

What happens after a pen test?

After successful completion, the ethical hacker will share findings with the target company’s security team. This information is then used to implement security improvements to address any vulnerabilities discovered during the test.

How are exploits used in penetration testing?

For the purposes of discovering vulnerabilities. Exploits in pen tests are designed not to cause any real harm or compromise any systems. Companies may use specific exploits, like phishing or SQL injections, that they deem a high risk to assess their cybersecurity posture.

Just about every organization should consider penetration testing to be a mandatory, ongoing cybersecurity activity. Working closely with a penetration testing partner like Varonis will help you streamline the process, efficiently identify vulnerabilities, and implement risk mitigation technologies so that when hackers do try to gain access to your systems, you’ve already plugged the gaps.

What should I do now?

Below are three ways you can continue your journey to reduce data risk at your company:


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