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

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

Correct Answer: B

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

Correct Answer: D

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

Correct Answer: C

One of the reasons for the increase in attacks on IACS is the availability of information and tools that can be used to exploit vulnerabilities in these systems. The Internet provides a platform for hackers, researchers, and activists to share their knowledge and techniques for compromising IACS. Some examples of such information and tools are: Stuxnet: A sophisticated malware that targeted the Iranian nuclear program in 2010. It exploited four zero-day vulnerabilities in Windows and Siemens software to infect and manipulate the programmable logic controllers (PLCs) that controlled the centrifuges. Stuxnet was widely analyzed and reported by the media and security experts, and its source code was leaked online1. Metasploit: A popular penetration testing framework that contains modules for exploiting various IACS components and protocols. For instance, Metasploit includes modules for attacking Modbus, DNP3, OPC, and Siemens S7 devices2. Shodan: A search engine that allows users to find devices connected to the Internet, such as webcams, routers, printers, and IACS components. Shodan can reveal the location, model, firmware, and configuration of these devices, which can be used by attackers to identify potential targets and vulnerabilities3. ICS-CERT: A website that provides alerts, advisories, and reports on IACS security issues and incidents. ICS-CERT also publishes vulnerability notes and mitigation recommendations for various IACS products and vendors4. These sources of information and tools can be useful for legitimate purposes, such as security testing, research, and education, but they can also be misused by malicious actors who want to disrupt, damage, or steal from IACS. Therefore, IACS owners and operators should be aware of the threats and risks posed by the Internet and implement appropriate security measures to protect their systems. References:

Correct Answer: A

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 and Scoring | Centraleyes4

Correct Answer: D

An intrusion detection system (IDS) is a network security tool that monitors network traffic and devices for known malicious activity, suspicious activity or security policy violations. The IDS sends alerts to IT and security teams when it detects any security risks and threats. However, an IDS does not block or prevent the malicious activity, it only detects and reports it. Therefore, an IDS is not the lock on the door for networks and computer systems, nor is it effective against all vulnerabilities in networks and computer systems. An IDS can be combined with an intrusion prevention system (IPS) to block the malicious activity in real time. References: What is Intrusion Detection Systems (IDS)? How does it Work? | Fortinet1 Intrusion Detection System (IDS) - GeeksforGeeks2 What is an intrusion detection system (IDS)? - IBM3

Correct Answer: B

Security Levels (SLs) are a way of expressing the security performance of an industrial automation and control system (IACS) or its components. SLs are broken down into three types: target, capability, and achieved1. Target SL is the level of security performance that is required for a system or component to protect against a specific threat scenario. The target SL is determined by conducting a risk assessment that considers the likelihood and impact of potential security

incidents1.

Capability SL is the level of security performance that a system or component can provide based on its design and implementation. The capability SL is determined by evaluating the security functions and features of the system or component

against a set of security requirements1.

Achieved SL is the level of security performance that a system or component actually provides in its operational environment. The achieved SL is determined by verifying that the system or component is properly installed, configured,

maintained, and monitored1.

References: ISA/IEC 62443 Standards to Secure Your Industrial Control System, page 3- 4.

Correct Answer: B

A security conduit is a logical or physical grouping of communication channels connecting two or more zones that share common security requirements1. A zone is a grouping of systems and components based on their functional, logical, and physical relationship that share common security requirements1. Therefore, a security conduit consists of assets that enable or facilitate communication between zones, such as wiring, routers, switches, and network managementdevices. Controllers, sensors, transmitters, and final control elements are examples of assets that belong to a zone, not a conduit. Ferrous, thickwall, and threaded conduit including raceways are physical structures that may enclose or protect wiring, but they are not part of the communication channels themselves. Power lines, cabinet enclosures, and protective grounds are also not part of the communication channels, but rather provide power or protection to the assets in a zone or a conduit. References: 1: Key Concepts of ISA/IEC 62443: Zones and Security Levels | Dragos

Correct Answer: C

According to the ISA/IEC 62443 Cybersecurity Fundamentals Specialist resources, patches are software updates that fix bugs, vulnerabilities, or improve performance of a system. Patches are classified into three categories based on their urgency and impact: low, medium, and high. Low priority patches are those that have minimal or no impact on the system functionality or security, and can be applied at the next scheduled maintenance. Medium priority patches are those that have moderate impact on the system functionality or security, and should be applied within a reasonable time frame, such as three months. High priority patches are those that have significant or criticalimpact on the system functionality or security, and should be applied as soon as possible, preferably at the first unscheduled outage. Applying patches in a timely manner is a best practice for maintaining the security and reliability of an industrial automation and control system (IACS). References: ISA/IEC 62443 Cybersecurity Fundamentals Specialist Study Guide, Section 4.3.2, Patch Management 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 5.3.2.2, Patch management ISA/IEC 62443-3-3:2013, Security for industrial automation and control systems - Part 3-3: System security requirements and security levels, Clause 4.3.3.6.2, Patch management