Penetration Testing | Pen Testing

What is Penetration Testing?

Penetration testing (often called pen testing) is a proactive cybersecurity practice used to evaluate the security of systems, networks, applications, or devices by simulating real-world cyberattacks. Authorized security professionals attempt to exploit vulnerabilities—such as misconfigurations, software flaws, or weak access controls—to determine how an attacker could gain unauthorized access, disrupt operations, or steal data.

The goal of penetration testing is not just to find vulnerabilities, but to demonstrate real risk by showing what could actually be compromised and how. Results are documented in a detailed report that prioritizes risks, explains potential impact, and provides clear remediation recommendations. Penetration testing is commonly used to support regulatory compliance, strengthen security programs, and validate the effectiveness of existing security controls before attackers can exploit weaknesses.

Why is Penetration Testing Important?

Penetration testing is important because it helps organizations identify and address security weaknesses before they can be exploited by real attackers. By simulating real-world cyberattacks, penetration testing reveals how vulnerabilities could be used to gain unauthorized access, disrupt systems, or expose sensitive data—providing a clear picture of actual risk rather than theoretical threats.

In addition, penetration testing supports regulatory and compliance requirements, helps validate the effectiveness of existing security controls, and strengthens overall cybersecurity posture. The insights gained allow organizations to prioritize remediation efforts, reduce the likelihood of costly breaches, protect brand reputation, and maintain trust with customers, partners, and regulators.

What regulatory and compliance requirements are supported by Penetration Testing?

Penetration testing supports a wide range of regulatory and compliance requirements across industries by demonstrating that security controls are effective and vulnerabilities are actively managed. Some of the most widely recognized frameworks and regulations that commonly require or strongly recommend penetration testing include:

• PCI DSS (Payment Card Industry Data Security Standard) – Requires regular penetration testing to protect cardholder data and validate network and application security controls.
• ISO/IEC 27001 – Supports information security risk management by validating controls within an Information Security Management System (ISMS).
• SOC 2 (Service Organization Controls) – Helps demonstrate the effectiveness of security controls aligned to the Trust Services Criteria, particularly Security and Availability.
• HIPAA (Health Insurance Portability and Accountability Act) – Supports safeguards for protecting electronic protected health information (ePHI) in healthcare systems.
• GDPR (General Data Protection Regulation) – Helps organizations identify and reduce risks to personal data through proactive security testing.
• NIST Cybersecurity Framework & NIST SP 800-series – Supports risk assessments and continuous security improvement practices commonly used by U.S. organizations.
• ISO/SAE 21434 (Automotive Cybersecurity) – Supports cybersecurity risk validation for road vehicles through vulnerability and attack path testing.
• FDA Cybersecurity Guidance (Medical Devices) – Helps manufacturers demonstrate cybersecurity risk management and vulnerability assessment activities.
• CMMC / DFARS (Defense Supply Chain) – Supports security testing requirements for organizations handling controlled unclassified information (CUI).

By aligning penetration testing with these standards and regulations, organizations can demonstrate due diligence, reduce compliance risk, and provide documented evidence of their commitment to cybersecurity best practices.

Types of Penetration Testing

There are several types of penetration testing, each designed to evaluate security from a different perspective or attack surface. Organizations often use a combination of these approaches to gain comprehensive coverage.

By Target / Scope

Network Penetration Testing

Network Penetration Testing is a controlled cybersecurity assessment that evaluates the security of an organization's network infrastructure by simulating real-world attacks. The goal is to identify vulnerabilities, misconfigurations, and weaknesses that could be exploited by attackers to gain unauthorized access to systems, data, or network resources.

During a network penetration test, ethical hackers attempt to exploit flaws in components such as firewalls, routers, switches, servers, wireless networks, and network services. This may include testing for open ports, weak credentials, unpatched systems, insecure protocols, and improper network segmentation. Testing can be performed from an external perspective (simulating an internet-based attacker) or an internal perspective (simulating a malicious insider or a compromised internal system).

Application Penetration Testing

Application Penetration Testing (often called app pentesting) is a security assessment process used to identify and exploit vulnerabilities in software applications before attackers can. It simulates real-world cyberattacks to evaluate how well an application can withstand threats and to uncover weaknesses that could lead to data breaches, system compromise, or service disruption.

Application penetration testing focuses on applications such as web apps, mobile apps, APIs, and desktop software. Security professionals analyze the application from both an external attacker's perspective and, when appropriate, an internal or authenticated user's viewpoint. Testing typically examines areas like authentication and authorization, input validation, session management, data handling, and integration points with other systems. The goal of application penetration testing is not only to find technical flaws—such as SQL injection, cross-site scripting (XSS), or insecure APIs—but also to understand their business impact.

Cloud Penetration Testing

Cloud Penetration Testing is a security assessment that evaluates the resilience of cloud-based environments against real-world cyberattacks. It involves authorized, simulated attacks on cloud infrastructure, applications, and services to identify vulnerabilities that could be exploited by malicious actors. Unlike traditional penetration testing, cloud penetration testing focuses on environments hosted on platforms such as AWS, Microsoft Azure, and Google Cloud. It examines cloud-specific risks including misconfigured storage buckets, insecure identity and access management (IAM) controls, exposed APIs, weak network segmentation, and improper use of cloud services.

The goal of cloud penetration testing is to validate the effectiveness of security controls, uncover configuration and design weaknesses, and assess how well an organization's cloud environment can prevent, detect, and respond to attacks.

Wireless Penetration Testing

Wireless Penetration Testing is a security assessment that evaluates the strength and resilience of an organization's wireless networks against potential cyberattacks. It involves simulating real-world attacks on Wi-Fi and other wireless technologies to identify vulnerabilities that could allow unauthorized access, data interception, or network compromise.

During a wireless penetration test, security professionals assess elements such as wireless access points, network configurations, encryption protocols, authentication mechanisms, and user behavior. Common activities include attempting to exploit weak passwords, outdated encryption (such as WEP), misconfigured access points, rogue or unauthorized devices, and vulnerabilities in guest or employee wireless networks.

The goal of Wireless Penetration Testing is to uncover security gaps before attackers do, helping organizations strengthen wireless defenses, protect sensitive data, and maintain compliance with security standards and regulatory requirements.

IoT / Embedded Systems Penetration Testing

IoT / Embedded Systems Penetration Testing is a specialized form of security testing that evaluates the security of Internet of Things (IoT) devices and embedded systems by simulating real-world cyberattacks. Its goal is to identify vulnerabilities in hardware, firmware, software, and communications that could be exploited to compromise device functionality, data, safety, or connected networks.

Unlike traditional IT penetration testing, IoT and embedded systems testing focuses on devices with constrained resources, specialized hardware, proprietary protocols, and long operational lifecycles—such as smart devices, industrial controllers, medical devices, automotive components, and connected building products.

OT / ICS Penetration Testing

OT / ICS Penetration Testing (Operational Technology / Industrial Control Systems Penetration Testing) is a specialized form of cybersecurity testing designed to evaluate the security of systems that monitor and control physical industrial processes. Unlike traditional IT penetration testing—which focuses on data, applications, and networks—OT/ICS penetration testing targets industrial environments where safety, availability, and reliability are critical.

OT/ICS penetration testing simulates real-world cyberattacks against industrial systems to identify vulnerabilities that could lead to:

• Process disruption or downtime
• Safety incidents
• Equipment damage
• Environmental harm
• Regulatory or compliance failures

The goal is to safely validate security weaknesses without interrupting operations or putting people at risk.

Intertek's approach to Penetration Testing

Intertek's penetration tests are delivered by experienced and qualified testers following an agreed methodology and using safe and proven tools. Intertek will provide you with a prioritized list of security weaknesses alongside cost effective actions to improve security.

Network penetration testing can help you address both assurance and certification needs:

• Assurance - Enabling you to identify and mitigate the intrinsic risk in your networks, operations, supply chains and business processes
• Certification – Formally confirming that your products and services meet trusted external and internal standards (see dedicated section)

Tests can support you in securing a range of system types including:

• Web sites and applications
• Network and cloud infrastructure
• Workstations and mobile devices
• Connected devices (IoT)

Tests can be performed from an external perspective to target Internet facing systems, and from an internal perspective to assess servers and end user devices.

The objective of a penetration test assignment will be tailored to your requirements and may include:

• Network wide – targeting all systems to establish baseline security against your internet and internal footprint
• System focused – assessing the configuration of a new server build or web application release

Red Teaming

What is Red Teaming?

Red Teaming is an advanced form of penetration testing that simulates a real-world, goal-driven cyberattack against an organization. Instead of simply identifying vulnerabilities, a Red Team operates like an actual adversary—using a combination of technical attacks, social engineering, and physical or logical intrusion techniques—to achieve specific objectives, such as accessing sensitive data, compromising critical systems, or evading detection over an extended period.

Red Teaming is important because it tests not only technical defenses, but also an organization's people, processes, and incident response capabilities. It helps validate whether security teams (the “Blue Team”) can detect, respond to, and contain sophisticated threats in real time. The insights gained reveal gaps in monitoring, communication, and response workflows that traditional penetration tests may miss. By exposing how attacks unfold across the entire environment, Red Teaming enables organizations to strengthen resilience, improve threat detection, and better prepare for advanced, persistent cyber threats.

Intertek's Red Teaming Solutions

As well as 'traditional' pen testing, Intertek also provides Red Teaming services. A Red Team project closely simulates a real-world hack, with Intertek's experts assessing potential organizational weaknesses, gathering intelligence and then launching a mock cyber-attack in real time, using similar techniques to real hackers, such as phishing attacks. Because only the most senior members of the client are aware of the project, a Red Team project also exercises the client's internal cybersecurity team, providing invaluable practice in responding to sophisticated severe cyber-attacks.

Penetration Testing - Frequently Asked Questions (FAQs)