ISA ISA Certifications ISA-IEC-62443 Questions & Answers

• Question 11:

  Which is a physical layer standard for serial communications between two or more devices?

  Available Choices (select all choices that are correct)

  A. RS232

  B. RS235

  C. RS432

  D. RS435

  Correct Answer: A

  RS232 is a physical layer standard for serial communication between two or more devices. It defines the electrical characteristics, timing, and pinout of connectors for serial data transmission. RS232 is widely used in industrial communication devices, such as PLCs, measuring instruments, and network servers. RS232 allows only one master and one slave to communicate on each line, and operates in a full duplex mode. RS232 has lower transmission speed, shorter maximum cable length, and larger voltage swing than later standards such as RS422 and RS485123 References: 1: Basics of RS232, RS422, and RS485 Serial Communication 2: RS-232 - Wikipedia 3: RS232 Serial Communication Protocol: Basics, Working and Specifications

• Question 12:

  Which is a commonly used protocol for managing secure data transmission on the Internet?

  Available Choices (select all choices that are correct)

  A. Datagram Transport Layer Security (DTLS)

  B. Microsoft Point-to-Point Encryption

  C. Secure Telnet

  D. Secure Sockets Layer

  Correct Answer: AD

  Datagram Transport Layer Security (DTLS) and Secure Sockets Layer (SSL) are both commonly used protocols for managing secure data transmission on the Internet. DTLS is a variant of SSL that is designed to work over datagram protocols such as UDP, which are used for real-time applications such as voice and video. SSL is a protocol that provides encryption, authentication, and integrity for data transmitted over TCP, which is used for reliable and ordered delivery of data. Both DTLS and SSL use certificates and asymmetric cryptography to establish a secure session between the communicatingparties, and then use symmetric cryptography to encrypt the data exchanged. DTLS and SSL are widely used in web browsers, email clients, VPNs, and other applications that require secure communication over the Internet. References: ISA/IEC 62443 Standards to Secure Your Industrial Control System, Module 3: Introduction to Cryptography, pages 3-5 to 3-7 Using the ISA/IEC 62443 Standards to Secure Your Control System, Chapter 6: Securing Communications, pages 125-126

• Question 13:

  Which of the following is an element of monitoring and improving a CSMS?

  Available Choices (select all choices that are correct)

  A. Increase in staff training and security awareness

  B. Restricted access to the industrial control system to an as-needed basis

  C. Significant changes in identified risk round in periodic reassessments

  D. Review of system logs and other key data files

  Correct Answer: ACD

  According to the ISA/IEC 62443 Cybersecurity Fundamentals Specialist resources, a CSMS is a Cybersecurity Management System that defines the policies, procedures, and practices for managing the security of an industrial automation and control system (IACS). A CSMS should be monitored and improved continuously to ensure its effectiveness and alignment with the changing risk environment and business objectives. Some of the elements of monitoring and improving a CSMS are: Increase in staff training and security awareness: This element involves providing regular and updated training and awareness programs for the staff involved in the operation, maintenance, and security of the IACS. Training and awareness can help improve the skills, knowledge, and behavior of the staff, and reduce the likelihood and impact of human errors, negligence, or malicious actions. Training and awareness can also help foster a positive security culture and increase the staff's engagement and commitment to the CSMS12 Significant changes in identified risk found in periodic reassessments: This element involves conducting periodic risk assessments to identify and evaluate the current and emerging threats, vulnerabilities, and consequences that may affect the IACS. Risk assessments can help determine the appropriate security levels (SLs) and security requirements for the system under control (SuC) and its components. Risk assessments can also help identify any gaps or weaknesses in the existing security measures and controls, and prioritize the actions for risk mitigation or acceptance. Periodic risk assessments can help ensure that the CSMS is responsive and adaptive to the changing risk landscape and business needs13 Review of system logs and other key data files: This element involves collecting, analyzing, and reviewing the system logs and other key data files that record the events and activities related to the IACS. System logs and data files can provide valuable information and insights for security monitoring, detection, response, and recovery. They can also help identify any anomalies, incidents, or breaches that may compromise the security or performance of the IACS. System logs and data files can also help measure and evaluate the effectiveness and efficiency of the CSMS and its processes, and provide feedback and recommendations for improvement14 References: ISA/IEC 62443 Cybersecurity Fundamentals Specialist Study Guide, Section 4.3, Cybersecurity Management System (CSMS) ISA/IEC 62443-2-1:2009, Security for industrial automation and control systems - Part 2-1: Establishing an industrial automation and control systems security program, Clause 5.3.2.1, Training and awareness ISA/IEC 62443-3-2:2020, Security for industrial automation and control systems - Part 3-2: Security risk assessment for system design, Clause 4, Security risk assessment process ISA/IEC 62443-4-2:2019, Security for industrial automation and control systems - Part 4-2: Technical security requirements for IACS components, Clause 4.3.3.7, Audit and accountabilit

• Question 14:

  Which steps are part of implementing countermeasures?

  Available Choices (select all choices that are correct)

  A. Establish the risk tolerance and select common countermeasures.

  B. Establish the risk tolerance and update the business continuity plan.

  C. Select common countermeasures and update the business continuity plan.

  D. Select common countermeasures and collaborate with stakeholders.

  Correct Answer: A

  According to the ISA/IEC 62443-3-2 standard, implementing countermeasures is one of the steps in the security risk assessment for system design. The standard defines a comprehensive set of engineering measures to guide organizations through the process of assessing the risk of a particular industrial automation and control system (IACS) and identifying and applying security countermeasures to reduce that risk to tolerable levels. The standard recommends the following steps for implementing countermeasures: Establish the risk tolerance: This step involves determining the acceptable level of risk for the organization and the system under consideration, based on the business objectives, legal and regulatory requirements, and stakeholder expectations. The risktolerance can be expressed as a target security level (SL-T) for each zone or conduit in the system. Select common countermeasures: This step involves selecting the appropriate security countermeasures for each zone or conduit, based on the SL-T and the existing security level (SL-A) of the system. The standard provides a list of common countermeasures for each security level, covering the domains of physical security, network security, system security, and application security. The selected countermeasures should be documented and justified in the security risk assessment report. References: ISA/IEC 62443 Cybersecurity Series Designated as IEC Horizontal Standards, Cybersecurity Risk Assessment According to ISA/IEC 62443-3-2

• Question 15:

  Which of the following is an industry sector-specific standard?

  Available Choices (select all choices that are correct)

  A. ISA-62443 (EC 62443)

  B. NIST SP800-82

  C. API 1164

  D. D. ISO 27001

  Correct Answer: C

  API 1164 is an industry sector-specific standard that provides guidance on the cybersecurity of pipeline supervisory control and data acquisition (SCADA) systems. API stands for American Petroleum Institute, which is the largest U.S. trade association for the oil and natural gas industry. API 1164 was first published in 2004 and revised in 2009 and 2021. The latest version of the standard aligns with the ISA/IEC 62443 series of standards and incorporates the concepts of security levels, zones, and conduits. API 1164 covers the security lifecycle of pipeline SCADA systems, from risk assessment and policy development to implementation and maintenance. The standard also defines roles and responsibilities, security requirements, security controls, and security assessment methods for pipeline SCADA systems. References: API 1164: Pipeline SCADA Security, Fourth Edition, September 2021 ISA/IEC 62443 Cybersecurity Fundamentals Specialist Study Guide, Section 2.2.2, Industry Sector-Specific Standards ISA/IEC 62443 Cybersecurity Fundamentals Specialist Exam Specification, Section 2.2.2, Industry Sector-Specific Standards

• Question 16:

  Which of the following is an activity that should trigger a review of the CSMS?

  Available Choices (select all choices that are correct)

  A. Budgeting

  B. New technical controls

  C. Organizational restructuring

  D. Security incident exposing previously unknown risk.

  Correct Answer: BCD

  According to the ISA/IEC 62443-2-1 standard, a review of the CSMS should be triggered by any changes that affect the cybersecurity risk of the industrial automation and control system (IACS), such as new technical controls, organizational restructuring, or security incidents1. Budgeting is not a trigger for CSMS review, unless it impacts the cybersecurity risk level or the CSMS itself2. References: 1: ISA/IEC 62443-2-1:2010, Section 4.3.3.3 2: A Practical Approach to Adopting the IEC 62443 Standards, ISAGCA Blog3

• Question 17:

  FILL IN THE BLANK

  Who must be included in a training and security awareness program?

  Available Choices (select all choices that are correct)

  O A. Vendors and suppliers

  O B. Employees

  A. All personnel

  B. Temporary staff

  Correct Answer:

  Modbus over Ethernet, also known as Modbus/TCP, is a protocol that encapsulates the Modbus/RTU data string inside the data section of the TCP frame. It then sets up a client/server exchange between nodes, using TCP/IP addressing to establish connections1. This makes it easy to manage in a firewall, because the firewall can filter the traffic based on the source and destination IP addresses and the TCP port number. The default TCP port for Modbus/TCP is 502, but it can be changed if needed. Modbus/TCP does not use any other ports or protocols, so the firewall rules can be simple and specific. References:

  8: Open Modbus/TCP Specification, RTA Automation, 2010. [9]: Modbus Application Protocol Specification V1.1b3, Modbus Organization, 2012.

• Question 18:

  What is defined as the hardware and software components of an IACS?

  Available Choices (select all choices that are correct) A. COTS software and hardware

  B. Electronic security

  C. Control system

  D. Cybersecuritv

  Correct Answer: C

  According to the ISA/IEC 62443-1-1 standard, an industrial automation and control system (IACS) is defined as a collection of personnel, hardware, and software that can affect or influence the safe, secure, and reliable operation of an

  industrial process. The hardware and software components of an IACS include the control system, which is the combination of control devices, networks, and applications that perform the control functions for the industrial process. The control

  system may consist of various types of devices, such as distributed control systems (DCS), programmable logic controllers (PLC), supervisory control and data acquisition (SCADA) systems, human-machine interfaces (HMI), remote terminal

  units (RTU), intelligent electronic devices (IED), sensors, actuators, and other field devices. The control system may also use commercial off-the-shelf (COTS) software and hardware, such as operating systems, databases, firewalls, routers,

  switches, and servers, to support the control functions and communication.

  References:

  ISA/IEC 62443-1-1:2009, Security for industrial automation and control systems - Part 1-1: Terminology, concepts and models, Clause 3.2.11 ISA/IEC 62443-2-1:2010, Security for industrial automation and control systems - Part 2-1:

  Establishing an industrial automation and control systems security program, Clause 3.2.12

• Question 19:

  Which is the BEST practice when establishing security zones?

  Available Choices (select all choices that are correct)

  A. Security zones should contain assets that share common security requirements.

  B. Security zones should align with physical network segments.

  C. Assets within the same logical communication network should be in the same security zone.

  D. All components in a large or complex system should be in the same security zone.

  Correct Answer: A

  Security zones are logical groupings of assets that share common security requirements based on factors such as criticality, consequence, vulnerability, and threat. Security zones are used to apply the principle of defense in depth, which means creating multiple layers of protection to prevent or mitigate cyberattacks. By creating security zones, asset owners can isolate the most critical or sensitive assets from the less critical or sensitive ones, and apply different levels of security controls to each zone according to the risk assessment. Security zones are not necessarily aligned with physical network segments, as assets within the same network may have different security requirements. For example, a network segment may contain both a safety instrumented system (SIS) and a human-machine interface (HMI), but the SIS has a higher security requirement than the HMI. Therefore, the SIS and the HMI should be in different security zones, even if they are in the same network segment. Similarly, assetswithin the same logical communication network may not have the same security requirements, and therefore should not be in the same security zone. For example, a logical communication network may span across multiple physical locations, such as a plant and a corporate office, but the assets in the plant may have higher security requirements than the assets in the office. Therefore, the assets in the plant and the office should be in different security zones, even if they are in the same logical communication network. Finally, all components in a large or complex system should not be in the same security zone, as this would create a single point of failure and expose the entire system to potential cyberattacks. Instead, the components should be divided into smaller and simpler security zones, based on their security requirements, and the communication between the zones should be controlled by conduits. Conduits are logical or physical connections between security zones that allow data flow and access control. Conduits should be designed to minimize the attack surface and the potential impact of cyberattacks, by applying security controls such as firewalls, encryption, authentication, and authorization. References: How to Define Zones and Conduits1 Securing industrial networks: What is ISA/IEC 62443?2 ISA/IEC 62443 Series of Standards3

• Question 20:

  Which statement is TRUE regarding Intrusion Detection Systems (IDS)?

  Available Choices (select all choices that are correct)

  A. Modern IDS recognize IACS devices by default.

  B. They are very inexpensive to design and deploy.

  C. They are effective against known vulnerabilities.

  D. They require a small amount of care and feeding

  Correct Answer: C

  Intrusion detection systems (IDS) are tools that monitor network traffic and detect suspicious or malicious activity based on predefined rules or signatures. They are effective against known vulnerabilities, as they can alert the system administrators or security personnel when they encounter a match with a known attack pattern or behavior. However, IDS have some limitations and challenges, especially when applied to industrial automation and control systems (IACS). Some of these are: Modern IDS do not recognize IACS devices by default, as they are designed for general-purpose IT networks and protocols. Therefore, they may generate false positives or negatives when dealing with IACS-specific devices, protocols, or traffic patterns. To overcome this, IDS need to be customized or adapted to the IACS environment and context, which may require additional expertise and resources. They are not very inexpensive to design and deploy, as they require careful planning, configuration, testing, and maintenance. They also need to be integrated with other security tools and processes, such as firewalls, antivirus, patch management, incident response, etc.Moreover, they may introduce additional costs and risks, such as network performance degradation, data privacy issues, or legal liabilities. They are not effective against unknown or zero-day vulnerabilities, as they rely on predefined rules or signatures that may not cover all possible attack scenarios or techniques. Therefore, they may fail to detect novel or sophisticated attacks that exploit new or undiscovered vulnerabilities. To mitigate this, IDS need to be complemented with other security measures, such as anomaly detection, threat intelligence, or machine learning. They require a significant amount of care and feeding, as they need to be constantly updated, tuned, and monitored. They also generate a large amount of data and alerts, which may overwhelm the system administrators or security personnel. Therefore, they need to be supported by adequate tools and processes, such as data analysis, alert filtering, prioritization, correlation, or visualization. References: ISA/IEC 62443-2-1:2010 - Establishing an industrial automation and control system security program, ISA/IEC 62443-3-3:2013 - System security requirements and security levels, ISA/IEC 62443 Cybersecurity Fundamentals Specialist Training Course, [Enhancing Modbus/TCP-Based Industrial Automation and Control Systems Security Using Intrusion Detection Systems]