ISA-IEC-62443 Exam Dumps - ISA Cybersecurity Questions and Answers

ISO/IEC 27001 is the international standard that defines requirements for establishing, implementing, maintaining, and continually improving an Information Security Management System (ISMS) across an organization.

Step 1: Scope of ISO/IEC 27001

ISO/IEC 27001 applies broadly to all information assets, including IT systems, business processes, and organizational data, regardless of industry.

Step 2: Contrast with ISA/IEC 62443

ISA/IEC 62443 focuses specifically on Industrial Automation and Control Systems, addressing OT-specific risks such as safety, availability, and real-time constraints. While 62443-2-1 aligns with ISMS principles, it is not a general-purpose ISMS standard.

Step 3: Complementary use

Organizations commonly use ISO/IEC 27001 for enterprise-wide information security and ISA/IEC 62443 for OT/IACS environments.

Thus, the standard focused on protecting sensitive information across all organizational systems via an ISMS is ISO/IEC 27001.

According to ISA/IEC 62443-3-2, the risk analysis phase in the IACS security lifecycle includes both the business rationale and the risk identification and classification. This ensures that risk decisions are based not only on technical vulnerability but also on business impact and operational context.

“The risk analysis process includes identification and classification of risks based on a defined business rationale. This ensures that the protection requirements are aligned with the organization’s risk tolerance and operational priorities.”

— ISA/IEC 62443-3-2:2020, Section 6.4 – Risk Assessment and SL Targeting

The term business rationale refers to understanding the value and criticality of the asset or system in order to make informed security decisions.

 A recommended default rule for IACS firewalls is to block all traffic by default, and then allow only the necessary and authorized traffic based on the security policy and the zone and conduit model. This is also known as the principle of least privilege, which means granting the minimum access required for a legitimate purpose. Blocking all traffic by default provides a higher level of security and reduces the attack surface of the IACS network. The other choices are not recommended default rules for IACS firewalls, as they may expose the IACS network to unnecessary risks. Allowing all traffic by default would defeat the purpose of a firewall, as it would not filter any malicious or unwanted traffic. Allowing IACS devices to access the Internet would expose them to potential cyber threats, such as malware, phishing, or denial-of-service attacks. Allowing traffic directly from the IACS network to the enterprise network would bypass the demilitarized zone (DMZ), which is a buffer zone that isolates the IACS network from the enterprise network and hosts services that need to communicate between them. References:

ISA/IEC 62443 Standards to Secure Your Industrial Control System training course1

ISA/IEC 62443 Cybersecurity Fundamentals Specialist Study Guide2

Using the ISA/IEC 62443 Standard to Secure Your Control Systems3

A significant challenge with firewalls in industrial environments is deciding how they should be configured. The complexity arises from needing to balance operational requirements (such as process data flow) with security needs (such as blocking unauthorized access). Misconfiguration can lead either to security gaps or to unnecessary operational disruptions. Firewalls can filter many types of traffic (not just HTTP) and while updates are important, configuration is the biggest ongoing challenge.

The ISA99 Committee (which develops the ISA/IEC 62443 series) clearly outlines four key consequences of compromising an Industrial Automation and Control System (IACS):

Endangerment of public or employee safety

Loss of public confidence

Violation of regulatory requirements

Loss of proprietary or confidential information

Economic and operational losses

“Increased product sales” is not listed — in fact, a compromise would likely result in the opposite, such as brand damage and loss of customer trust.

“The scope of the ISA99 Committee includes addressing risks such as the endangerment of public safety, loss of information, and economic harm arising from cyber incidents affecting IACS.”

— ISA/IEC 62443-1-1:2007, Clause 1 – Scope and Purpose

Even the most modern and sophisticated safety systems can be defeated by an attacker. This statement is validated by the discovery of malware specifically targeting safety instrumented systems (SIS), such as the "Triton/Trisis" malware that compromised the SIS of a petrochemical plant. Safety systems, while designed as independent protection layers, are not immune to cybersecurity vulnerabilities and require specific countermeasures. Integration, such as using Modbus TCP, does not inherently reduce risk to a tolerable level without additional controls.

 The ISASecure conformance certification program is managed by the Security Compliance Institute (ISCI), a non-profit organization established in 2007 by a group of industry stakeholders, including end users, suppliers, and integrators. ISCI’s mission is to provide a common industry-accepted set of device and process requirements that drive device security, simplifying procurement for asset owners and device assurance for equipment vendors12. References: 1: ISASecure - IEC 62443 Conformance Certification - Official Site 2: Certifications - ISASecure

ISA/IEC 62443-2-1 explicitly requires that the IACS Security Program be integrated into the organization’s overall management structure.

Step 1: Integration principle

The standard states that IACS security must align with business processes, governance, and enterprise security management rather than operate in isolation.

Step 2: Alignment with ISMS

Where an Information Security Management System (ISMS) exists, the IACS SP should be embedded within it to ensure consistent risk management, policy enforcement, and continuous improvement.

Step 3: Why other options are incorrect

Standalone security programs create silos. Full outsourcing violates asset owner accountability. Purely technical approaches ignore human and process factors.

Step 4: Operational outcome

Embedding the SP ensures sustainability, consistency, and executive oversight.

Therefore, the correct answer is by embedding it into organizational processes and the ISMS.

According to the ISA/IEC 62443 series, it is the asset owner's responsibility to determine what level of residual cybersecurity risk is acceptable after mitigation strategies are applied. This value becomes a key input in defining security levels and selecting controls.

“The asset owner is responsible for defining the tolerable residual risk and establishing acceptable security levels based on business impact and risk tolerance.”

— ISA/IEC 62443-3-2:2020, Clause 6.4.2 – Risk Evaluation Inputs

This forms the foundation for SL-T (Target Security Level) determination.

ISA/IEC 62443 is developed within the international standards system, where national participation is coordinated through National Standardization Bodies (NSBs). These organizations represent their country’s interests in international standards committees and manage the adoption of international standards at the national level.

Step 1: Role of a National Standardization Body

An NSB acts as the official representative of a country within international standards organizations such as IEC and ISO. It coordinates national input, votes on standards, and nominates experts to technical committees.

Step 2: Adoption of international standards

NSBs are responsible for adopting international standards as national standards, often with minimal or no modification. This enables consistent global alignment while supporting local implementation.

Step 3: Why other options are incorrect

Global SDOs develop standards internationally but do not represent individual countries.

Regulatory agencies enforce laws, not standards.

Industry consortia represent private-sector interests, not national positions.

Thus, the correct role is National Standardization Body.