Free Practice Questions for ISA ISA-IEC-62443 Exam

Modbus is defined as a serial communication protocol widely used in industrial environments to enable communication among devices such as PLCs, sensors, and actuators.

From ISA/IEC 62443-1-1 (Terminology, Concepts, and Models), Modbus is mentioned in the context of communication protocols:

"Many IACS use legacy communication protocols (e.g., Modbus, DNP3) that were not originally designed with cybersecurity in mind."

Modbus was developed in 1979 by Modicon and operates over serial lines (RS-232, RS-485) or over Ethernet as Modbus TCP/IP. It follows a master/slave or client/server architecture.

Incorrect Options:

A. A programming language – Modbus is not a language; it’s a protocol.

B. A network security standard – It lacks built-in security; it is a communication protocol, not a security standard.

C. A type of industrial machinery – It facilitates communication between machinery, but is not machinery itself.

 According to the ISA/IEC 62443 Cybersecurity Fundamentals Specialist course, establishing policy, organization, and awareness is one of the four steps of the IACS cybersecurity lifecycle. This step involves defining the cybersecurity policies, roles, and responsibilities, as well as communicating them to the relevant stakeholders. It also involves establishing the risk tolerance level, which is the acceptable level of risk for the organization. Communicating policies and establishing the risk tolerance are both activities that are part of this step. Identifying detailed vulnerabilities and implementing countermeasures are activities that belong to the next steps of the lifecycle, which are assessing the current situation and implementing the cybersecurity program, respectively. References: ISA/IEC 62443 Cybersecurity Fundamentals Specialist course, Module 2: IACS Cybersecurity Lifecycle1

ICS-CERT (Industrial Control Systems Cyber Emergency Response Team) issues alerts to inform critical infrastructure owners and operators about newly discovered vulnerabilities, threats, and mitigation strategies.

“ICS-CERT Alerts provide timely information to critical infrastructure owners and operators concerning current security issues, vulnerabilities, and exploits.”

— ICS-CERT Advisory Documentation (now under CISA)

Alerts may be sector-wide or vendor-specific, and are part of the U.S. Department of Homeland Security’s proactive cyber defense strategy.

Clarification of Options:

Not specific to the energy sector only (D is too narrow)

Not promotional in nature (eliminates A and B)

The Security Program (SP) portfolio is the correct foundational document for an evolving IACS cybersecurity approach according to the ISA/IEC 62443 family of standards. ISA/IEC 62443 is explicitly designed around the concept of continuous risk management and lifecycle-based cybersecurity, rather than static or one-time security implementations.

Step 1: Role of the Security Program (SP)

ISA/IEC 62443-2-1 defines the requirements for establishing, implementing, maintaining, and continuously improving an IACS Cybersecurity Management System. The Security Program provides organizational governance through policies, roles, responsibilities, procedures, training, incident handling, change management, and continuous improvement activities. These elements ensure cybersecurity adapts as threats, vulnerabilities, and system configurations evolve.

Step 2: Need for an evolving security approach

The standard recognizes that IACS environments are long-lived and subject to changing operational conditions, emerging threat actors, and new vulnerabilities. Therefore, cybersecurity must be managed as an ongoing process. The SP portfolio enables periodic reassessment of risks, updates to controls, and improvements to security processes throughout the system lifecycle.

Step 3: Relationship between SP and SPS

IEC 62443-2-2 introduces the Security Protection Scheme (SPS), which is a documented set of technical, procedural, and physical security measures selected to mitigate identified risks. However, the SPS is not the foundation; it is a product of the Security Program. The SP governs how the SPS is developed, implemented, operated, and modified over time.

Step 4: Elimination of incorrect options

“IEC 62443-2-2 only” is insufficient because it addresses SPS development without broader governance.

Corporate KPIs unrelated to IACS do not manage cybersecurity risk.

An SPS alone cannot evolve without programmatic oversight.

In alignment with the intent and structure of ISA/IEC 62443, the Security Program (SP) portfolio is the correct foundation for a cybersecurity plan that must continuously evolve.

A Local Area Network (LAN) is not a strategy for deploying a Wide Area Network (WAN). WAN deployment strategies include using the public Internet, private enterprise WANs, or carrier-managed WANs. LANs, by definition, serve local, not wide-area, connectivity. ISA/IEC 62443 standards refer to different strategies for extending network communications over broader geographic regions, but do not classify LAN as a WAN deployment option.

A Process Hazard Analysis (PHA) is a systematic method of identifying and evaluating the potential hazards associated with an industrial process. A PHA can help to identify the sources of cyber threats, the consequences of cyber incidents, and the existing safeguards and mitigation measures. A PHA is most frequently used as an input to a security risk assessment because it provides a comprehensive and structured overview of the process and its risks, which can then be used to determine the security level targets and security countermeasures for the industrial automation and control system (IACS). A PHA can also help to align the security objectives with the safety objectives of the process, and to ensure that the security measures do not compromise the safety or operability of the process. References:

ISA/IEC 62443 Standards to Secure Your Industrial Control System, page 10

Using the ISA/IEC 62443 Standard to Secure Your Control System, page 17

Phishing is a type of cyberattack that relies on a human weakness to succeed. Phishing is the practice of sending fraudulent emails or other messages that appear to come from a legitimate source, such as a bank, a government agency, or a trusted person, in order to trick the recipient into revealing sensitive information, such as passwords, credit card numbers, or personal details, or into clicking on malicious links or attachments that may install malware or ransomware on their devices. Phishing is a common and effective way of compromising the security of industrial automation and control systems (IACS), as it can bypass technical security measures by exploiting the human factor. Phishing can also be used to gain access to the IACS network, to conduct reconnaissance, to launch further attacks, or to cause damage or disruption to the IACS operations. The ISA/IEC 62443 series of standards recognize phishing as a potential threat vector for IACS and provide guidance and best practices on how to prevent, detect, and respond to phishing attacks. Some of the recommended countermeasures include:

Educating and training the IACS staff on how to recognize and avoid phishing emails and messages, and how to report any suspicious or malicious activity.

Implementing and enforcing policies and procedures for email and message security, such as using strong passwords, verifying the sender’s identity, and not opening or clicking on unknown or unsolicited links or attachments.

Applying technical security controls, such as antivirus software, firewalls, spam filters, encryption, and authentication, to protect the IACS devices and network from phishing attacks.

Monitoring and auditing the IACS network and devices for any signs of phishing attacks, such as anomalous or unauthorized traffic, connections, or activities, and taking appropriate actions to contain and mitigate the impact of any incidents. References:

ISA/IEC 62443-1-1:2009, Security for industrial automation and control systems - Part 1-1: Terminology, concepts and models1

ISA/IEC 62443-2-1:2009, Security for industrial automation and control systems - Part 2-1: Establishing an industrial automation and control systems security program2

ISA/IEC 62443-2-4:2015, Security for industrial automation and control systems - Part 2-4: Security program requirements for IACS service providers3

ISA/IEC 62443-3-3:2013, Security for industrial automation and control systems - Part 3-3: System security requirements and security levels4

ISA/IEC 62443-4-2:2019, Security for industrial automation and control systems - Part 4-2: Technical security requirements for IACS components5

Cybersecurity awareness programs are most effective when tailored to the organization’s audience, are aligned with corporate policies, and are communicated regularly. ISA/IEC 62443-2-1 emphasizes the importance of ongoing cybersecurity training and awareness, customized to different user roles, as a critical factor in reducing human-related security risks.

A Wide Area Network (WAN) is a communications system that covers a large geographic area, such as a city, a country, or even several countries or continents1. WANs are often used to connect local area networks (LANs) and other types of networks together, so that users and computers in one location can communicate with users and computers in other locations2. WANs use various communication infrastructures, such as public telephone lines, undersea cables, and communication satellites, to transmit data over long distances1. WANs are typically established with leased telecommunication circuits or less costly circuit switching or packet switching methods2. WANs are often built by Internet service providers, who provide connections from an organization’s LAN to the Internet2. The Internet itself may be considered a WAN2. References: Hardware and network technologies - CCEA LAN and WAN - BBC, Wide area network - Wikipedia.

ISA/IEC TR 62443-1-5 defines the rules for creating cybersecurity profiles. The key principle is preservation of standard integrity.

Step 1: Purpose of profiles

Profiles allow selection and scoping of existing requirements for specific industries or applications.

Step 2: Restriction on modification

The technical report explicitly states that no new security requirements may be added, and existing requirements must not be altered. This ensures interoperability, auditability, and certification consistency.

Step 3: Correct approach

Profiles may select, exclude, or contextualize requirements, but they cannot redefine them.

Therefore, Option C is correct.