How Internal Penetration Testing Can Identify Vulnerabilities

Cybersecurity | February 2, 2024

Hackers are getting smarter and smarter every year. Why not hire one to help your business improve security measures? This is essentially what penetration testing is.

Internal penetration testing specifically helps your business identify vulnerabilities due to access control issues, employees, and vendors. Because 88% of data breaches are caused by employee mistakes, this test cannot be understated.

How does internal penetration testing identify network vulnerabilities and security gaps? Keep reading to learn the answer and find out which industries can benefit.

What Is Penetration Testing?

Penetration testing can be implemented into your risk management strategy. Unlike traditional cybersecurity defenses, pen tests focus on prevention rather than remediating a security event.

Penetration tests are also different than vulnerability scans. An automated vulnerability assessment can identify:

  • Common misconfiguration errors
  • Known vulnerabilities
  • A lack of security controls

A penetration test, also known as ethical hacking or a white hat attack, is performed by a skilled tester who simulates a cyber attack. Testers will explore your system to identify security flaws and vulnerabilities.

The tester will find and investigate the potential effects of these flaws on your business network. They will also:

  • Review security awareness within the organization
  • Discover security policy errors
  • Identify compliance issues related to the relevant industry
  • Discover weaknesses in security controls

The goal of a pen test is to identify security weaknesses that a cyber attacker could exploit to compromise the system, demand a ransom, disrupt operations, or steal sensitive data.

During internal penetration testing, the tester might try to leverage these strategies:

  • Steal and use unencrypted passwords to access sensitive information
  • Send phishing emails to access critical accounts
  • Test employee security awareness
  • Engage in social engineering to convince an insider to reveal sensitive information

Following the test, the pen tester will prepare a detailed report of their findings. Security teams can then work to remediate exact exploits to prevent future problems.

Who Performs Internal Penetration Testing?

Penetration testing is completed by ethical hackers. They will methodically compromise a network to uncover security vulnerabilities before a cybercriminal does.

Skilled testers understand how to simulate real-world attacks. This provides valuable information on an organization’s cybersecurity posture.

Internal pen test teams are built by the business. The insider knowledge of the company allows them to create threat models that assess risk. Internal teams might overlook vulnerabilities that outside testers can catch.

Consider working with third-party ethical hackers who can identify vulnerabilities without a bias to internal assumptions. Their outside experience allows them to expose any overlooked security gaps missed by your internal team.

Types of Penetration Tests

The different types of penetration tests are based on the system that is getting tested. Opting for every pen test can cover your bases when you want your complete IT infrastructure checked. Here is a brief breakdown of each of them.

Network Pen Tests

An ethical hacker will test network security measures by hacking into the network using:

Network pen tests can be completed remotely.

Hardware Pen Tests

If your business uses a lot of internet-enabled devices, hardware pen tests can help you spot an unidentified weakness.

A tester will exploit gaps in security in networked printers, security cameras, smart home systems, etc.

Web and Mobile Application Pen Tests

Web and mobile application pen tests are straightforward. The tester will check the security of APIs, software, and web apps.

To find vulnerabilities in your company’s mobile app, the tester will try to compromise the app.

Wireless Pen Tests

A wireless pen test involves connecting to less secure and open hotspots, such as WiFi networks. This allows testers to understand how threats might exploit the enterprise network.

Physical Pen Tests

In a physical pen test, an internal tester will try to break into a physical space where business data may be present. They will try their best to get unauthorized access to physical assets and IT systems.

Testers may go as far as posing as a service technician or contractor. Your access control system must prevent them from gaining access.

The Stages of Identifying Vulnerabilities

Your business can use penetration testing to validate your cybersecurity plan against real-world attacks. A skilled pen tester and ethical hacker can safely compromise systems to uncover vulnerabilities that real hackers try to exploit.

Real internal penetration testing simulates motivated hackers’ procedures, techniques, and tactics. It involves the five phases outlined below.


The first step to identifying network vulnerabilities is planning. This is where the tester will define the rules of engagement, target systems, scope, and testing methodologies.

Testers will gather information regarding the business’s network infrastructure, digital assets, and web applications. This is open-source intelligence likely to be publicly available.


Hackers will begin to discover vulnerabilities by scanning Application Programming Interfaces (APIs), networks, applications, and wireless signals.

To create an inventory of security issues that they can exploit, they will perform non-intrusive vulnerability scanning.


Once vulnerabilities have been identified, the ethical hacker will attempt to exploit the holes in your security using these common techniques:

  • Cross-Site Scripting (XSS)
  • Structured Query Language (SQL) injection
  • Password cracking
  • Social engineering
  • Data exfiltration

Hackers will attempt to achieve escalation of privilege and denial of service as well.


When hackers have access to your network, they will maintain a hold on your system to model Advanced Persistent Threats (APTs).

The goal of this step of the process is to see how well your security controls detect and respond to the cyberattack.


An internal pen tester will document which vulnerabilities were successfully exploited.

With this data, they can provide guidance and risk assessments to strengthen cyber defenses. This will help you improve your overall security against real-world criminals.

Internal Pen Testing vs. External Pen Testing

Internal and external pen testing can identify business network vulnerabilities. Every pen test involves scoping, intelligence gathering, threat modeling, exploitation, and analysis.

Internal testing evaluates insider risks from:

  • Rogue employees
  • Social engineering
  • Compromised accounts
  • Phishing

An internal pen test is best for evaluating identity and access management, security monitoring, and network segmentation. An internal pen test is usually completed after an external pen test.

External testing, in contrast, targets public-facing internet systems like web apps, websites, APIs, email servers, and network infrastructure. It focuses on breaching vulnerabilities remotely.

Opting for both internal and external pen testing can provide you with a complete view of how secure your business is.

Are Internal Threats Serious?

Many organizations fail to put effort into internal security threats. Internal threats from careless employees, malicious insiders, clients or customers, or insecure third-party vendors are equally as serious as external threats.

Insider incidents can cause data breaches in any industry. The threats commonly come from:

  • Weak access controls
  • Weak or shared passwords
  • Network misconfigurations
  • Ransomware attacks
  • Insecure file sharing or unencrypted data
  • Lack of awareness of phishing or social engineering

To address these threats, internal penetration is necessary.

Blind and Double-Blind Pen Testing

Blind pen testing doesn’t inform the testing team of any details. This models undetected cyberattacks, like real-world threats.

Double-blind pen testing keeps the testers and the defenders unaware. Your employees will learn how to detect and respond to new vulnerabilities on a whim.

Double-blind testing is used to evaluate readiness against zero-day attacks that your business is unaware of.

When to Complete an Internal Pen Test

Internal penetration always makes sense if you have a digital work environment. Online threats are financially motivated and ruthless.

Keep your security and compliance goals at the foundation of your IT needs. An internal pen test can be a critical piece of this puzzle.

If you believe an internal pen test is insufficient to test your overall security posture, consider an external pen test as well.

Internal pen tests take a lot of effort from one or more of your employees. You can opt to use automation tools to cover more of your bases. Pen testing cannot be completely automated, you’ll need a blend of manual and automated services.

Industries That Benefit From Pen Testing

Penetration testing can help various industries maintain compliance. Many industries require businesses to adhere to specific regulations and compliance standards.

Pen testing can keep the healthcare industry compliant with the Health Insurance Portability and Accountability Act (HIPAA). Cyberattacks on healthcare providers are consistent because this industry maintains large amounts of sensitive data.

To remain HIPAA compliant, healthcare businesses need to perform regular technological tests of their data security, in which penetration testing can be a valuable tool.

Lawyers also carry a lot of sensitive client information. Pen testing can keep the legal industry compliant, as well as the manufacturing, non-profit, and financial industries.

Secure Your IT System With EMPIST 360

IT services are critical for businesses looking to stay compliant and protected in a digital world. Leveraging external and internal penetration testing can improve your risk management strategy tenfold.

An internal team and ethical hackers can help identify vulnerabilities within your business network.

Whether your business is in the healthcare or legal industry, pen testing can help. Our team of experts at EMPIST can provide technical and digital solutions for your business.

Our full-service technology company offers a range of services, including penetration testing. Ready to have the peace of mind your business deserves? Get in touch with us today.