Free Practice Questions for ISA ISA-IEC-62443 Exam

 Access control is the process of granting or denying specific requests to obtain and use information and related information processing services. It is one of the foundational requirements (FRs) of the ISA/IEC 62443 standards for securing industrial automation and control systems (IACSs). According to the ISA/IEC 62443-3-3 standard, access control includes the following system requirements (SRs):

SR 1.1: Identification and authentication control

SR 1.2: Use control

SR 1.3: System integrity

SR 1.4: Data confidentiality

SR 1.5: Restricted data flow

SR 1.6: Timely response to events

SR 1.7: Resource availability

Among these SRs, the ones that are most related to the critical variables of account management and password strength are SR 1.1 and SR 1.2. SR 1.1 requires that the IACS shall provide the capability to uniquely identify and authenticate all users, processes, and devices that attempt to establish a logical connection to the system. This means that the IACS should have a robust account management system that can create, modify, delete, and monitor user accounts and their privileges. It also means that the IACS should enforce strong password policies that can prevent unauthorized access or compromise of user credentials. Password strength refers to the level of difficulty for an attacker to guess or crack a password. It depends on factors such as length, complexity, randomness, and uniqueness of the password.

SR 1.2 requires that the IACS shall provide the capability to enforce the use of logical connections in accordance with the security policy of the organization. This means that the IACS should have a mechanism to control the access rights and permissions of users, processes, and devices based on their roles, responsibilities, and needs. It also means that the IACS should have a mechanism to audit and log the activities and events related to access control, such as successful or failed login attempts, password changes, privilege escalations, or unauthorized actions.

Therefore, account management and password strength are the critical variables related to access control, as they directly affect the identification, authentication, and authorization of users, processes, and devices in the IACS.

A security policy refers to internal rules that govern how an organization protects critical system resources, such as industrial control systems (ICS). A security policy defines the objectives, scope, roles, responsibilities, and requirements for securing the ICS environment, as well as the procedures and guidelines for implementing, monitoring, and enforcing the security measures. A security policy also establishes the baseline for assessing and managing the security risks to the ICS, and for ensuring compliance with relevant standards, regulations, and best practices. A security policy is a key component of the ICS security program, and it should be documented, communicated, and reviewed regularly.

The other choices are not correct because:

A. Formal guidance. Formal guidance refers to external sources of information and recommendations that can help an organization improve its ICS security posture, such as standards, frameworks, guidelines, and best practices. Formal guidance is not an internal rule, but rather a reference that can be used to develop, implement, and evaluate the security policy and controls. For example, the ISA/IEC 62443 series of standards provide formal guidance on how to secure ICS from cyber threats1.

B. Legislation. Legislation refers to external laws and regulations that impose legal obligations and penalties on an organization for its ICS security performance, such as the NERC CIP standards for the electric sector2, or the EU NIS Directive for critical infrastructure operators3. Legislation is not an internal rule, but rather a compliance requirement that must be met by the organization. Legislation may also influence the security policy and controls, as the organization needs to align its security objectives and practices with the legal expectations and consequences.

D. Code of conduct. A code of conduct refers to a set of ethical principles and values that guide the behavior and decision-making of an organization and its employees, such as honesty, integrity, respect, and accountability. A code of conduct is not an internal rule for protecting critical system resources, but rather a general norm for conducting business and maintaining a positive reputation. A code of conduct may also support the security policy and culture, as it can foster a sense of responsibility and trust among the ICS stakeholders.

 A cyber attack is an attempt to compromise the confidentiality, integrity, or availability of a computer system or network by exploiting its vulnerabilities. A cyber attack can be launched from various entry points, which are the pathways that allow an attacker to access a target system or network. According to the ISA/IEC 62443-3-2 standard, which defines a method for conducting a security risk assessment for industrial automation and control systems (IACS), some of the possible entry points for a cyber attack are:

LAN: A local area network (LAN) is a network that connects devices within a limited geographic area, such as a building or a campus. A LAN can be an entry point for a cyber attack if an attacker gains physical or logical access to the network devices, such as switches, routers, firewalls, or servers. An attacker can use various techniques to access a LAN, such as network scanning, spoofing, sniffing, or hijacking. An attacker can also exploit vulnerabilities in the network protocols, services, or applications that run on the LAN. A cyber attack on a LAN can affect the communication and operation of the devices and systems connected to the network, such as IACS.

Portable media: Portable media are removable storage devices that can be used to transfer data between different systems or devices, such as USB flash drives, CDs, DVDs, or external hard drives. Portable media can be an entry point for a cyber attack if an attacker uses them to introduce malicious code or data into a target system or device. An attacker can use various techniques to infect portable media, such as autorun, social engineering, or physical tampering. An attacker can also exploit vulnerabilities in the operating systems, drivers, or applications that interact with portable media. A cyber attack using portable media can affect the functionality and security of the systems or devices that use them, such as IACS.

Wireless: Wireless is a technology that enables communication and data transmission without physical wires or cables, such as Wi-Fi, Bluetooth, or cellular networks. Wireless can be an entry point for a cyber attack if an attacker intercepts, modifies, or disrupts the wireless signals or data. An attacker can use various techniques to access wireless networks or devices, such as cracking, jamming, or eavesdropping. An attacker can also exploit vulnerabilities in the wireless protocols, standards, or encryption methods. A cyber attack on wireless can affect the availability and reliability of the wireless communication and data transmission, such as IACS.

Therefore, LAN, portable media, and wireless are three possible entry points that could be used for launching a cyber attack. References:

Cybersecurity Risk Assessment According to ISA/IEC 62443-3-21

ISA/IEC 62443 Series of Standards2

API 1164 is an industry sector-specific standard that provides guidance on the cybersecurity of pipeline supervisory control and data acquisition (SCADA) systems. API stands for American Petroleum Institute, which is the largest U.S. trade association for the oil and natural gas industry. API 1164 was first published in 2004 and revised in 2009 and 2021. The latest version of the standard aligns with the ISA/IEC 62443 series of standards and incorporates the concepts of security levels, zones, and conduits. API 1164 covers the security lifecycle of pipeline SCADA systems, from risk assessment and policy development to implementation and maintenance. The standard also defines roles and responsibilities, security requirements, security controls, and security assessment methods for pipeline SCADA systems.

According to ISA/IEC 62443-1-1, a vulnerability is defined as “the potential for violation of security,” which means a weakness or gap in protection efforts that could be exploited by threats to gain unauthorized access or cause harm to an IACS. It does not specifically mean an event (B) or a result (D), and it is broader than just management flaws (A). The identification and management of vulnerabilities are key steps in risk assessment and mitigation in the 62443 framework.

Programmable Logic Controllers (PLCs) were originally designed to replace relay-based control systems in industrial automation. Early manufacturing and process control systems relied on hard-wired relays, timers, and sequencers, which were inflexible and difficult to modify. PLCs offered a software-based alternative that could easily be reprogrammed for various automation tasks, making plant operations more efficient and flexible. Their purpose was not specifically to enhance network security or Ethernet functionality, but rather to modernize and simplify control logic implementation.

Packet filter, application proxy, and stateful inspection are all recognized types or classes of firewalls in both IT and industrial control environments. A network monitor, on the other hand, is not considered a firewall but rather a tool for observing and analyzing network traffic. It does not provide firewall-like controls for blocking or allowing traffic.

ISA/IEC 62443 emphasizes that physical security and cybersecurity are interdependent and must complement each other to provide robust protection for industrial automation and control systems (IACS). Physical security measures (like locks, fences, access cards) protect against unauthorized physical access, while cybersecurity measures protect against digital threats. Both must work together; for example, a cyber attacker might gain physical access to a control cabinet or a physical intruder might exploit weak network security.