ISA ISA-IEC-62443 Online Practice Questions and Exam Preparation

ISA ISA-IEC-62443 Online Questions & Answers

• Question 231:

  After receiving an approved patch from the IACS vendor, what is BEST practice for the asset owner to follow?

  A. If a low priority, there is no need to apply the patch.
  B. If a medium priority, schedule the installation within three months after receipt.
  C. If a high priority, apply the patch at the first unscheduled outage.
  D. If no problems are experienced with the current IACS, it is not necessary to apply the patch.
  C. If a high priority, apply the patch at the first unscheduled outage.

  ---

  Per ISA/IEC 62443-2-1 and 62443-2-3, proper patch management is part of operational cybersecurity. For high-priority or critical security patches, the best practice is to apply the patch at the earliest possible opportunity, often during the next available unscheduled or scheduled outage. "Asset owners shall define procedures for evaluating and applying patches based on criticality and potential impact. High-priority patches should be applied at the earliest opportunity, preferably at the first available system downtime."

  -ISA/IEC 62443-2-3:2015, Clause 6.1 - Patch Management Process Waiting unnecessarily or skipping patches because "nothing is broken" is not acceptable in security-critical environments.

  References: ISA/IEC 62443-2-1:2010 - Clause 4.4.3.2 ISA/IEC 62443-2-3:2015 - Patch Management Guidance

• Question 232:

  What are the two sublayers of Layer 2?

  Available Choices (select all choices that are correct)

  A. HIDS and NIDS
  B. LLC and MAC
  C. OPC and DCOM
  D. VLAN and VPN
  B. LLC and MAC

  ---

  .Layer 2 of the OSI model is the data link layer, which is responsible for transferring data frames between nodes on a network segment. The data link layer is divided into two sublayers: logical link control (LLC) and media access control (MAC). The LLC sublayer deals with issues common to both dedicated and broadcast links, such as framing, flow control, and error control. The MAC sublayer deals with issues specific to broadcast links, such as how to access the shared medium and avoid collisions. The LLC and MAC sublayers are not related to the ISA/IEC 62443 cybersecurity standards, which focus on the security of industrial automation and control systems (IACS).

  References: https://www.baeldung.com/cs/data-link-sub-layers https://bing.com/search?q=Layer+2+sublayers

• Question 233:

  Which communication path presents the HIGHEST risk if left uncontrolled?

  A. Controller to sensor
  B. HMI to controller
  C. Enterprise network to control network
  D. Safety controller to actuator
  C. Enterprise network to control network

  ---

  Uncontrolled communication between enterprise IT networks and control networks introduces significant cyber risk due to exposure to external threats and broader attack surfaces.

  References: ISA/IEC 62443-3-3:2013 ?SR 5.1 ISA/IEC 62443-3-2:2020 ?Clause 5.3

• Question 234:

  How does ISA/IEC 62443-2-1 suggest integrating the IACS Security Program (SP) within an organization?

  A. As a standalone system unrelated to other processes
  B. Outsourcing all security responsibilities to third parties
  C. By embedding it into organizational processes and the ISMS
  D. Only focusing on technical controls without process integration
  C. By embedding it into organizational processes and the ISMS

  ---

  ISA/IEC 62443-2-1 clearly recommends that the IACS Security Program (SP) be fully embedded into existing organizational processes, including alignment with the Information Security Management System (ISMS), if present. "The IACS security program shall be integrated with the organization's overall management systems and processes, including those defined in the ISMS (e.g., ISO/IEC 27001)."

  - ISA/IEC 62443-2-1:2010, Clause 4.2.1 - Integration of Security Program This ensures that security is a sustained operational priority and not a separate or siloed initiative.

  References: ISA/IEC 62443-2-1:2010 - Clause 4.2.1 ISO/IEC 27001 - ISMS alignment

• Question 235:

  What are the connections between security zones called? Available Choices (select all choices that are correct)

  A. Firewalls
  B. Tunnels
  C. Pathways
  D. Conduits
  D. Conduits

  ---

  According to the ISA/IEC 62443 standard, the connections between security zones are called conduits. A conduit is defined as a logical or physical grouping of communication channels connecting two or more zones that share common security requirements. A conduit can be used to control and monitor the data flow between zones, and to apply security measures such as encryption, authentication, filtering, or logging. A conduit can also be used to isolate zones from each other in case of a security breach or incident. A conduit can be implemented using various technologies, such as firewalls, routers, switches, cables, or wireless links. However, these technologies are not synonymous with conduits, as they are only components of a conduit. A firewall, for example, can be used to create multiple conduits between different zones, or to protect a single zone from external threats. Therefore, the other options (firewalls, tunnels, and pathways) are not correct names for the connections between security zones.

  References: ISA/IEC 62443-3-2:2016 - Security for industrial automation and control systems - Part 3-2: Security risk assessment and system design1 ISA/IEC 62443-3-3:2013 - Security for industrial automation and control systems - Part 3-3: System security requirements and security levels2 Zones and Conduits | Tofino Industrial Security Solution3 Key Concepts of ISA/IEC 62443: Zones and Security Levels | Dragos4

• Question 236:

  Why is OPC Classic considered firewall unfriendly?

  A. It allows use of only port 80.
  B. It dynamically assigns several ports.
  C. It is an obsolete communication standard.
  D. It works with control devices from different manufacturers.
  B. It dynamically assigns several ports.

  ---

  OPC Classic uses Microsoft's DCOM (Distributed Component Object Model) for communication, which dynamically opens multiple ports, making it extremely difficult to manage with firewalls. "OPC Classic is firewall-unfriendly because DCOM requires dynamic port negotiation, making it difficult to define consistent firewall rules."

  - ISA/IEC 62443-3-3:2013, Annex A - Communication Protocols and Security Concerns

  This lack of port predictability presents a significant security and operational risk, which led to the development of OPC UA, which uses fixed ports and supports encryption.

  References: ISA/IEC 62443-3-3 - Annex A OPC Foundation Security Guidelines

• Question 237:

  Under User Access Control (SP Element 6), which of the following is included in USER 1 - Identification and Authentication?

  A. Backup restoration
  B. Password protection
  C. Mutual authentication
  D. Incident handling and response
  B. Password protection

  ---

  SP Element 6 in ISA/IEC 62443-2-1 covers User Access Control. Within this, USER 1 - Identification and Authentication includes controls such as: Unique user identification Password and credential management Authentication mechanisms "USER 1 defines policies for individual user identification and password protection to enforce accountability and prevent unauthorized access."

  -ISA/IEC 62443-2-1:2010, Clause 4.3.4 - SP Element 6

  "Password protection" is a core component of this control, while other options (like incident handling or backup) fall under different SP elements.

  References: ISA/IEC 62443-2-1:2010 - SP Element 6, USER 1 ISA/IEC 62443-1-1 - Definitions of authentication and access control