ISC Systems Security Engineering Foundations — Timed 20 Questions

Question 1

When designing a secure system architecture, which TWO of the following are primary considerations for achieving the principle of 'Defense in Depth'?

Accepted Answer

Applying security controls at multiple architectural layers. Defense in depth relies on layering security controls so that a single failure does not result in a total system compromise.

Answer

Relying solely on perimeter authentication

Answer

Maximizing system throughput by minimizing encryption

Answer

Implementing a single high-availability firewall

Question 2

You are integrating security requirements into the Systems Engineering V-Model. At which stage should the Information Systems Security Engineer (ISSE) define the security functional requirements to ensure traceability to the system architecture?

Accepted Answer

Requirements Analysis. Security requirements must be defined during the Requirements Analysis phase to ensure they are baked into the system design rather than added as an afterthought.

Answer

Detailed Design

Answer

System Integration and Testing

Answer

Operational Maintenance

Question 3

An organization is adopting a DevSecOps model. To ensure security engineering principles are met, which tool should be integrated into the CI/CD pipeline to automate the detection of vulnerabilities in proprietary code during the 'Build' stage?

Accepted Answer

SAST (Static Application Security Testing). Static Application Security Testing (SAST) tools analyze source code for security vulnerabilities without executing the code, making them ideal for the build stage.

Answer

DAST (Dynamic Application Security Testing)

Answer

IDS (Intrusion Detection System)

Answer

SIEM (Security Information and Event Management)

Question 4

During the 'Engineering Process Integration' phase, an ISSE identifies that the legacy system lacks support for modern TLS 1.3 encryption. What is the most appropriate engineering response?

Accepted Answer

Document the risk and implement compensating controls. The ISSE should perform a gap analysis to determine if a compensating control can mitigate the risk until the legacy system can be upgraded or replaced.

Answer

Forcibly inject TLS 1.3 into the binary

Answer

Ignore the finding because it is a legacy system

Answer

Immediately shut down the system

Question 5

When applying NIST SP 800-160 Systems Security Engineering principles, which THREE activities are critical during the 'System Design' phase to ensure confidentiality and integrity?

Accepted Answer

Identifying security-relevant system components. System design involves defining architectural components, securing interfaces, and establishing trust boundaries.

Answer

Developing incident response plans

Answer

Performing final penetration testing

Question 6

When using the STRIDE threat modeling methodology, which security principle does 'Tampering' specifically attempt to violate?

Accepted Answer

Integrity. Tampering threats target the Integrity aspect of the CIA triad by attempting to modify data or system configurations.

Answer

Confidentiality

Answer

Availability

Answer

Non-repudiation

Question 7

In the context of the System Development Life Cycle (SDLC), what is the primary purpose of a security control baseline?

Accepted Answer

To define the minimum security requirements for a system category. A baseline establishes the minimum set of security controls required to protect the system based on its impact level.

Answer

To replace the need for a risk assessment

Answer

To audit employee performance

Answer

To automate the deployment of security patches

Question 8

Which engineering document should be created during the early stages of the system lifecycle to define the security-relevant mission goals and constraints?

Accepted Answer

System Security Plan (SSP). The System Security Plan (SSP) or an equivalent Concept of Operations for Security (SecConOps) defines the security mission and constraints at the start.

Answer

Patch Management Policy

Answer

Incident Response Plan

Answer

Vulnerability Assessment Report

Question 9

What is the primary benefit of modularity in secure systems design?

Accepted Answer

Facilitates security analysis and component isolation. Modularity allows for fault isolation and easier security verification of individual components.

Answer

Reduces the total number of lines of code

Answer

Eliminates the need for API gateways

Answer

Guarantees the system cannot be hacked

Question 10

When applying the principle of Least Privilege, which technical implementation is most effective in a microservices architecture?

Accepted Answer

Attribute-Based Access Control (ABAC). Attribute-Based Access Control (ABAC) provides granular control based on user, environment, and resource attributes, ideal for complex microservice environments.

Answer

Role-Based Access Control (RBAC)

Answer

Discretionary Access Control (DAC)

Answer

Mandatory Access Control (MAC)

Question 11

Which THREE factors must be evaluated when determining if a system component is 'security-critical'?

Accepted Answer

Its role in processing sensitive information. Security-critical components are those that enforce policy, handle sensitive data, or provide security functions.

Answer

Its location in the physical facility

Answer

Its cost of procurement

Question 12

Which TWO items should be included in a 'Security Requirements Traceability Matrix' (SRTM) to ensure comprehensive engineering coverage?

Accepted Answer

The corresponding system component or design element. An SRTM maps requirements to design elements and test cases to ensure no security requirement is overlooked.

Answer

The vendor contact information

Answer

The employee performance review score

Answer

The marketing department's sales forecast

Question 13

In the context of the NIST Cybersecurity Framework, which function is specifically supported by the 'Systems Security Engineering' process during the 'Identify' stage?

Accepted Answer

Risk Assessment (ID.RA). Systems Engineering identifies assets and risks, which aligns with the 'Identify' function in the NIST CSF.

Answer

Recovery Planning (RC.RP)

Answer

Access Control (PR.AC)

Answer

Detection Processes (DE.DP)

Question 14

When conducting a security assessment of a system's 'Trusted Computing Base' (TCB), what is the most important attribute to verify?

Accepted Answer

Verifiability of security functions. The TCB is the set of all hardware, software, and firmware components that are critical to the security of the system; it must be verifiable and correct.

Answer

System performance metrics

Answer

User-friendliness of the interface

Answer

The versioning history of the software

Question 15

Which THREE activities are essential when conducting a 'Security Impact Analysis' for a proposed system change?

Accepted Answer

Reviewing existing security controls for degradation. Impact analysis evaluates how changes affect existing controls, risk profiles, and system integrity.

Answer

Replacing all hardware in the data center

Answer

Renaming the system server hostname

Question 16

Which security model is specifically designed to prevent the unauthorized flow of information from high-security levels to low-security levels (no read up, no write down)?

Accepted Answer

Bell-LaPadula model. The Bell-LaPadula model focuses on confidentiality by enforcing the 'no read up, no write down' rules.

Answer

Clark-Wilson model

Answer

Biba model

Answer

Brewer-Nash model

Question 17

When integrating security into the requirements phase, what is the value of 'Misuse Cases'?

Accepted Answer

They provide insights into potential system threats. Misuse cases define what a malicious actor might try to do to the system, helping to derive security requirements.

Answer

They automate the generation of firewall rules

Answer

They replace the need for unit testing

Answer

They track the progress of development sprints

Question 18

Which THREE of the following are considered 'Common Criteria' (ISO/IEC 15408) elements for evaluating the security functionality of a product?

Accepted Answer

Protection Profile (PP). Common Criteria uses Protection Profiles and Security Targets to define and evaluate security requirements.

Answer

Sales and Marketing Specification

Answer

Employee Training Records

Question 19

In the systems engineering V-model, how does 'Verification' differ from 'Validation'?

Accepted Answer

Verification confirms the system meets specifications; Validation confirms it meets mission goals. Verification ensures the system is built correctly (conformance to requirements), while validation ensures the correct system is built (meeting user needs).

Answer

Verification is for security; Validation is for performance

Answer

Verification is done by vendors, Validation by end-users

Answer

Verification is for software, Validation is for hardware

Question 20

Which TWO of the following are valid methods for maintaining the integrity of system design documentation throughout the system lifecycle?

Accepted Answer

Version control systems (e.g., Git). Documentation must be version-controlled and subject to strict change management to remain accurate.

Answer

Relying on verbal updates from team members

Answer

Posting documents on a public forum

Answer

Periodic manual document destruction