ISA Cybersecurity ISA-IEC-62443 Questions & Answers

• Question 1:

  Which is a reason for and physical security regulations meeting a mixed resistance?

  Available Choices (select all choices that are correct)

  A. Regulations are voluntary documents.

  B. Regulations contain only informative elements.

  C. Cybersecurity risks can best be managed individually and in isolation.

  D. There are a limited number of enforced cybersecurity and physical security regulations.

  Correct Answer: D

  Cybersecurity and physical security regulations are intended to provide guidance and requirements for protecting industrial control systems from various threats and risks. However, these regulations may face mixed resistance from different stakeholders for various reasons. One of the reasons is that there are a limited number of enforced cybersecurity and physical security regulations, especially at the international level. This means that some regions or countries may have more stringent or comprehensive regulations than others, creating inconsistencies and challenges for cross- border cooperation and compliance. Moreover, some regulations may be outdated or not aligned with the current best practices and standards, such as ISA/IEC 62443, which may limit their effectiveness and applicability. Therefore, some organizations may prefer to follow voluntary standards or frameworks, such as ISA/IEC 62443, rather than mandatory regulations, as they may offer more flexibility and adaptability to the specific needs and contexts of each industrial control system. References: ISA/IEC 62443 Standards to Secure Your Industrial Control System, page 3 Using the ISA/IEC 62443 Standard to Secure Your Control System, page 9

• Question 2:

  Which is the BEST deployment system for malicious code protection?

  Available Choices (select all choices that are correct)

  A. Network segmentation

  B. IACS protocol converters

  C. Application whitelistinq (AWL) OD.

  D. Zones and conduits

  Correct Answer: C

  Application whitelisting (AWL) is a technique that allows only authorized applications to run on a system, and blocks any unauthorized or malicious code from executing. AWL is one of the most effective methods for preventing malware infections and reducing the attack surface of a system. AWL can be implemented at different levels, such as the operating system, the network, or the application itself. AWL is especially useful for industrial automation and control systems (IACS), which often run on legacy or proprietary platforms that are not compatible with traditional antivirus software or other security solutions. AWL can also help protect IACS from zero-day attacks, which exploit unknown vulnerabilities that have not been patched or detected by security vendors. AWL is recommended by the ISA/IEC 62443 standards as a key component of malicious code protection for IACS. According to the standards, AWL should be applied to all IACS components that support it, and should be configured and maintained according to the security policies and procedures of the organization. AWL should also be complemented by other security measures, such as network segmentation, zones and conduits, and patch management, to provide a defense-in-depth approach to IACS security. References: ISA/IEC 62443-3-3:2013, System security requirements and security levels, Section 5.2.3.41 ISA/IEC 62443-2-1:2010, Establishing an industrial automation and control systems security program, Section 4.3.3.6.42 ISA/IEC 62443-4-2:2019, Technical security requirements for IACS components, Section 4.2.3.43 ISA/IEC 62443-3-2:2020, Security risk assessment for system design, Section 7.3.3.44 ISA/IEC 62443-4-1:2018, Product development requirements, Section 5.2.3.45

• Question 3:

  Why is patch management more difficult for IACS than for business systems?

  Available Choices (select all choices that are correct)

  A. Overtime pay is required for technicians.

  B. Many more approvals are required.

  C. Patching a live automation system can create safety risks.

  D. Business systems automatically update.

  Correct Answer: C

  Patch management is the process of applying software updates to fix security vulnerabilities, improve functionality, or enhance performance. Patch management is an essential part of cybersecurity, as unpatched systems can be exploited by

  malicious actors. However, patch management for industrial automation and control systems (IACS) is more challenging than for business systems, because patching a live automation system can create safety risks. According to the ISA/IEC

  62443 standards, patching an IACS may have the following potential impacts1:

  Patching may introduce new vulnerabilities or errors that compromise the availability, integrity, or confidentiality of the IACS. Patching may affect the functionality or performance of the IACS, causing unexpected or undesired behavior, such

  as process shutdowns, slowdowns, or failures.

  Patching may require downtime or reduced operation of the IACS, which may affect production, quality, or profitability.

  Patching may require additional resources, such as personnel, equipment, or testing facilities, which may not be readily available or affordable. Therefore, patch management for IACS requires careful planning, testing, and validation before

  applying patches to the operational environment. The ISA/IEC 62443 standards provide guidance and best practices for patch management in the IACS environment, such as1:

  Establishing a patch management program that defines roles, responsibilities, policies, and procedures for patching IACS components and systems. Identifying and prioritizing the IACS assets that need patching, based on their criticality,

  vulnerability, and risk level.

  Evaluating and verifying the patches for compatibility, functionality, and security before applying them to the IACS.

  Implementing and documenting the patching process, including backup, recovery, and rollback procedures, in case of patch failure or adverse effects. Monitoring and auditing the patching activities and outcomes, and reporting any issues or

  incidents.

  References: 1: ISA TR62443-2-3 - Security for industrial automation and control systems, Part 2-3: Patch management in the IACS environment

• Question 4:

  Which is a common pitfall when initiating a CSMS program?

  Available Choices (select all choices that are correct)

  A. Organizational lack of communication

  B. Failure to relate to the mission of the organization

  C. Insufficient documentation due to lack of good follow-up

  D. Immediate jump into detailed risk assessment

  Correct Answer: D

  "A common pitfall is to attempt to initiate a CSMS program without at least a high-level rationale that relates cyber security to the specific organization and its mission." A CSMS program is a Cybersecurity Management System program that follows the IEC 62443 standards for securing industrial control systems (ICS)1. A common pitfall when initiating a CSMS program is D. Immediate jump into detailed risk assessment. This is because a detailed risk assessment requires a clear definition of the system under consideration (SuC), the allocation of IACS assets to zones and conduits, and the identification of threats, vulnerabilities, and consequences for each zone and conduit2. These steps are part of the assess phase of the CSMS program, which is the first phase of the security program development process2. However, before starting the assess phase, it is important to have the management team's support to ensure the CSMS program will have sufficient financial and organizational resources to implement necessary actions2. Therefore, jumping into detailed risk assessment without having the management buy-in is a common mistake that can jeopardize the success of the CSMS program.

• Question 5:

  What is the purpose of ISO/IEC 15408 (Common Criteria)?

  Available Choices (select all choices that are correct)

  A. To define a security management organization

  B. To describe a process for risk management

  C. To define a product development evaluation methodology

  D. To describe what constitutes a secure product

  Correct Answer: C

  ISO/IEC 15408, also known as the Common Criteria for Information Technology Security Evaluation, is an international standard that provides a framework for evaluating the security of IT products and systems. The purpose of the standard is to define a common set of requirements for the security functions and assurance measures of IT products and systems, and to establish a common methodology for conducting security evaluations. The standard allows users to specify their security needs and expectations in a Security Target (ST), which may be based on one or more Protection Profiles (PPs) that define security requirements for a class of products or systems. Vendors can then implement or claim compliance with the ST or PPs, and have their products or systems evaluated by independent testing laboratories against the security criteria defined in the standard. The standard also defines a scale of Evaluation Assurance Levels (EALs) that indicate the degree of confidence in the security of the evaluated product or system. The standard is intended to facilitate the development, procurement, and use of secure IT products and systems, and to promote the recognition and acceptance of evaluation results across different countries and regions. References: ISO/IEC 15408-1:2009 - Common Criteria Evaluation for IT Security - Nemko1 Common Criteria - Wikipedia2 ISO/IEC Standard 15408 -- ENISA3

• Question 6:

  Which of the following is the BEST example of detection-in-depth best practices?

  Available Choices (select all choices that are correct)

  A. Firewalls and unexpected protocols being used

  B. IDS sensors deployed within multiple zones in the production environment

  C. Role-based access control and unusual data transfer patterns

  D. Role-based access control and VPNs

  Correct Answer: D

  Packet filter firewalls are the simplest type of firewalls that examine each incoming packet and compare its source, destination, and ports with a predefined set of rules. If the packet matches the rules, it is allowed to pass through the firewall; otherwise, it is blocked or dropped. Packet filter firewalls do not inspect the packet structure, sequence, or content beyond the header information. They also do not keep track of the relationships between packets in a session, which means they cannot detect attacks that span multiple packets or connections. Packet filter firewalls are fast and efficient, but they have limited security capabilities and cannot protect against application-layer attacks or sophisticated threats. References: ISA/IEC 62443-3-3:2018, Section 4.2.3.2.11; ISA/IEC 62443 Cybersecurity Fundamentals Specialist Study Guide, Section 5.2.12

• Question 7:

  Which characteristic is MOST closely associated with the deployment of a demilitarized zone (DMZ)?

  Available Choices (select all choices that are correct)

  A. Level 4 systems must use the DMZ to communicate with Level 3 and below.

  B. Level 0 can only interact with Level 1 through the firewall.

  C. Internet access through the firewall is allowed.

  D. Email is prevented, thereby mitigating the risk of phishing attempts.

  Correct Answer: A

  According to the ISA/IEC 62443 standard, a demilitarized zone (DMZ) is a network segment that is logically between the internal and external networks, and its purpose is to enforce the internal network's information assurance policy for external information exchange and to provide external, untrusted sources with restricted access to releasable information while shielding the internal networks from external attacks1. The standard also defines five levels of network segmentation, from Level 0 (process) to Level 4 (enterprise), and recommends that Level 4 systems must use the DMZ to communicate with Level 3 (site control) and below, as shown in the figure below2. This way, the DMZ acts as a buffer zone that prevents direct access from the internet to the industrial control systems (ICS) and allows only authorized traffic to pass through the firewalls. References: 1: demilitarized zone (DMZ) - Glossary | CSRC 2: Industrial DMZ Infrastructure - Siemens

• Question 8:

  Which of the following attacks relies on a human weakness to succeed?

  Available Choices (select all choices that are correct)

  A. Denial-of-service

  B. Phishing

  C. Escalation-of-privileges

  D. Spoofing

  Correct Answer: B

  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

• Question 9:

  Which analysis method is MOST frequently used as an input to a security risk assessment?

  Available Choices (select all choices that are correct)

  A. Failure Mode and Effects Analysis

  B. Job Safety Analysis

  C. Process Hazard Analysis (PHA)

  D. System Safety Analysis(SSA)

  Correct Answer: C

  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

• Question 10:

  Which is one of the PRIMARY goals of providing a framework addressing secure product development life-cycle requirements?

  Available Choices (select all choices that are correct)

  A. Aligned development process

  B. Aligned needs of industrial users

  C. Well-documented security policies and procedures

  D. Defense-in-depth approach to designing

  Correct Answer: A

  One of the primary goals of providing a framework addressing secure product development life-cycle requirements is to ensure that the development process of industrial automation and control systems (IACS) products is aligned with the security objectives and requirements of the ISA/IEC 62443 series of standards. The framework defines a secure development life-cycle (SDL) that covers all the phases of product development, from security requirements definition, to secure design, implementation, verification, validation, defect management, patch management, and product end-of-life. The framework also provides guidance on how to document and demonstrate compliance with the SDL requirements, as well as how to assess the security performance of the products using security levels. By following the framework, product suppliers can improve the security of their products and reduce the risk of vulnerabilities and exploits that may compromise the safety, integrity, reliability, and security of IACS. References: ISA/IEC 62443-4-1:2018, Security for industrial automation and control systems - Part 4-1: Product security development life-cycle requirements1 ISA/IEC 62443-4-2:2019, Security for industrial automation and control systems - Part 4-2: Technical security requirements for IACS components2