Pass the ISA Cybersecurity ISA-IEC-62443 Questions and answers with ValidTests

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 comprehensiveregulations 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 Moreover, some regulations may be outdated or not aligned with the current best practices and standards, such as ISA/IEC 62443, which may limit their effectiveness and applicability.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

Defense in depth is a concept of cybersecurity that involves applying multiple layers of protection to a system or network, so that if one layer fails, another layer can prevent or mitigate an attack. Defense in depth is based on the principle that no single security measure is perfect or sufficient, and that multiple countermeasures can provide redundancy and diversity of defense. Defense in depth can also increase the cost and complexity for an attacker, as they have to overcome more obstacles and exploit more vulnerabilities to achieve their goals. Defense in depth is one of the key concepts of the ISA/IEC 62443 series of standards, which provide guidance and best practices for securing industrial automation and control systems (IACS). The standards recommend applying defense in depth strategies at different levels of an IACS, such as the network, the system, the component, and the policy and procedure level. The standards also define different zones and conduits within an IACS, which are logical or physical groupings of assets that share common security requirements and risk levels. By applying defense in depth strategies to each zone and conduit, the security of the entire IACS can be improved. References:

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

ISA/IEC 62443-3-3:2013, Security for industrial automation and control systems - Part 3-3: System security requirements and security levels2

ISA/IEC 62443-4-1:2018, Security for industrial automation and control systems - Part 4-1: Product security development life-cycle requirements3

ISA/IEC 62443-4-2:2019, Security for industrial automation and control systems - Part 4-2: Technical security requirements for IACS components4

 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.

 The risk analysis category of an IACS consists of two elements: business rationale and risk identification and classification1. Business rationale is the process of defining the scope, objectives, and criteria for the risk analysis, as well as the roles and responsibilities of the stakeholders involved. Risk identification and classification is the process of identifying the assets, threats, vulnerabilities, and consequences of a cyberattack on the IACS, and assigning a risk level to each scenario based on the likelihood and impact of the attack1. These elements are essential for establishing a baseline of the current risk posture of the IACS and determining the appropriate risk treatment measures to reduce the risk to an acceptable level. References: 1: ISA/IEC 62443-3-2:2020, Security for industrial automation and control systems - Part 3-2: Security risk assessment for system design, International Society of Automation, Research Triangle Park, NC, USA, 2020.

The ISA-99/IEC 62443 standards for industrial automation and control systems security categorize network and system components into different levels based on their operational context. The correct name from the provided options for one of these levels is Level 3: Operations Management. This level typically encompasses systems that manage production control systems, including batch management, production scheduling, and overall factory operations. The other levels listed, such as Supervisory Control and Process, refer to different aspects of the system but are not named correctly in the options provided. Level 1 is correctly referred to as "Basic Control," and Level 4 should be "Business Logistics" instead of "Process."

 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

The ISASecure Integrated Threat Analysis (ITA) Program is a certification scheme that certifies off-the-shelf automation and control systems to the ISA/IEC 62443 series of standards1. The ITA Program consists of three main components2:

Software Development Security Assurance (SDSA): This component evaluates the security lifecycle and practices of the product supplier, such as security requirements, design, implementation, verification, and maintenance. The SDSA certification is based on the ISA/IEC 62443-4-1 standard.

Functional Security Assessment (FSA): This component verifies the security functions and features implemented in the product, such as identification and authentication, access control, encryption, audit logging, and security management. The FSA certification is based on the ISA/IEC 62443-4-2 standard.

Communications Robustness Testing (CRT): This component tests the resilience of the product against network attacks, such as denial-of-service, fuzzing, spoofing, and replay. The CRT certification is based on the ISA/IEC 62443-4-2 and ISA/IEC 62443-3-3 standards .

References:

1: ISASecure - IEC 62443 Conformance Certification - Official Site

2: ISASecure - IEC 62443 Conformance Certification - Official Site

[3]: ISA/IEC 62443-4-1: Secure Product Development Lifecycle Requirements, ISA, 2018.

[4]: ISA/IEC 62443-4-2: Technical Security Requirements for IACS Components, ISA, 2019.

[5]: ISA/IEC 62443-4-2: Technical Security Requirements for IACS Components, ISA, 2019.

[6]: ISA/IEC 62443-3-3: System Security Requirements and Security Levels, ISA, 2013.

The NIST CSF is a voluntary framework that provides a set of standards, guidelines, and best practices to help organizations manage cybersecurity risks. The NIST CSF consists of five core functions: Identify, Protect, Detect, Respond, and Recover. Each function is further divided into categories and subcategories that describe specific outcomes and activities. The NIST CSF also provides informative references that link the subcategories to existing standards, guidelines, and practices that can help organizations achieve the desired outcomes. The informative references are not mandatory or exhaustive, but rather serve as examples of possible sources of guidance. The ISA 62443 standards are used as informative references in the NIST CSF v1.0 for several subcategories, especially in the Protect and Detect functions. The ISA 62443 standards are a series of standards that provide a framework for securing industrial automation and control systems (IACS). The ISA 62443 standards cover various aspects of IACS security, such as terminology, concepts, requirements, policies, procedures, and technical specifications. The ISA 62443 standards are aligned with the NIST CSF in terms of the core functions and the risk-based approach. Therefore, the ISA 62443 standards can provide useful guidance and best practices for organizations that use IACS and want to implement the NIST CSF. References:

NIST Cybersecurity Framework - Official Site1

Framework for Improving Critical Infrastructure Cybersecurity - Version 1.02

ISA/IEC 62443 Standards - Official Site3

ISA/IEC 62443 Compliance & Scoring | Centraleyes4

 The ISA/IEC 62443 standards are focused on industrial automation and control systems security. The assess phase within the ISA/IEC 62443 framework is designed to identify and analyze potential vulnerabilities in the industrial control system (ICS) environment. One of the key steps in this phase is the specification of cybersecurity requirements. Additionally, it involves the allocation of industrial automation and control system (IACS) assets to defined zones and conduits to manage and segregate the network and improve security. These measures help to ensure that security requirements are met and that the assets are protected according to their security needs. Therefore, the correct answer is B, which mentions both the cybersecurity requirements specification and the allocation of IACS assets to zones and conduits as part of the assess phase.

Asymmetric (public) key algorithms are a type of cryptographic algorithms that require more than one key. Asymmetric key algorithms use a pair of keys, one for encryption and one for decryption, that are mathematically related but not identical1. The encryption key is usually made public, while the decryption key is kept private. This allows anyone to encrypt a message using the public key, but only the intendedrecipient can decrypt it using the private key1. Asymmetric key algorithms are also known as public key algorithms or public key cryptography1. Asymmetric key algorithms are used for various purposes, such as digital signatures, key exchange, and encryption2. Some examples of asymmetric key algorithms are RSA, Diffie-Hellman, ElGamal, and Elliptic Curve Cryptography2.

References: Asymmetric Algorithm or Public Key Cryptography - IBM, Cryptography 101: Key Principles, Major Types, Use Cases & Algorithms | Splunk.