ISC CSSLP Exam Dumps & Practice Test Questions

Question 1:

As a network auditor examining a Windows-based infrastructure, you encounter challenges in detecting system faults and identifying network components.

What category of risk is most appropriately associated with this issue?

A. Residual risk
B. Secondary risk
C. Detection risk
D. Inherent risk

Correct Answer: C

Explanation:

In this scenario, the auditor’s difficulty in identifying faults or network components points directly to detection risk. Detection risk refers to the possibility that auditors may not discover existing issues, misconfigurations, or vulnerabilities during an audit, even though they exist within the system. This type of risk stems from limitations in the auditing process, such as ineffective tools, insufficient access, lack of system visibility, or even human error.

In network auditing, being able to recognize and understand faults is critical to identifying areas where security or performance is compromised. If the audit process fails to reveal these issues, it compromises the audit’s integrity and can allow existing vulnerabilities to persist undetected. This type of oversight is exactly what detection risk encompasses.

Let’s look at why the other options are incorrect in this context:

• Residual risk refers to the level of risk that remains after security measures and controls have been applied. It is the "leftover" risk that an organization must accept after attempting to mitigate threats. This concept is related to the outcome of risk management, not the process of discovering flaws during an audit.

• Secondary risk is risk that emerges as a consequence of implementing a risk response. For instance, if a control solution introduces a new system vulnerability or operational challenge, that resultant risk is secondary. It’s not applicable to the situation described, where the issue is about identifying current problems.
  
  

• Inherent risk is the natural level of risk that exists in an environment before any mitigation or controls are applied. Although it is foundational in understanding the baseline risk of a system, it doesn’t relate directly to the auditor’s capacity to uncover faults.

To summarize, detection risk captures the essence of the scenario: it is the risk that an audit fails to detect real, existing issues. This is a critical concept in both IT auditing and broader risk management frameworks, and in this case, it's the most accurate classification of the risk involved.

Question 2:

Under the National Information Assurance Certification and Accreditation Process (NIACAP), which individuals or roles are required participants in the system security assessment process? (Select all that apply)

A. Certification agent
B. Designated Approving Authority
C. Information System Program Manager
D. Information Assurance Manager
E. User representative

Correct Answers: A, B, C, E

Explanation:

The NIACAP was designed as a standardized framework to certify and accredit information systems that manage national security data. Though largely replaced by the Risk Management Framework (RMF), NIACAP remains foundational in understanding roles and responsibilities during system certification and authorization. The process requires active collaboration between multiple stakeholders to ensure a system meets the required security standards before it's approved for operational use.

Here’s a breakdown of the key participants:

• Certification Agent (A): This individual or team conducts the technical and procedural evaluation of the system. Their goal is to determine whether the system meets defined security requirements. Their findings form the basis for the final accreditation decision. The agent plays a critical role in identifying vulnerabilities, compliance gaps, and operational security concerns.

• Designated Approving Authority (DAA) (B): Now commonly known as the Authorizing Official (AO), the DAA is the senior official who reviews the certification documentation and decides whether to authorize the system’s operation. This decision hinges on whether the residual risks identified during the assessment are deemed acceptable.

• Information System (IS) Program Manager (C): Also called the System Owner, this person is responsible for the overall development and implementation of the system. They oversee the integration of security controls and ensure all documentation and testing is complete before certification begins. Their coordination with the certification agent and other stakeholders is vital to the success of the assessment.

• User Representative (E): Representing the system’s end-users, this role ensures that operational needs are met and user concerns are addressed. Their participation helps balance security requirements with real-world usability, ensuring the system supports mission goals without compromising protection.

Now consider the Information Assurance Manager (IAM) (D). While the IAM has a significant role in current security frameworks like RMF, under NIACAP, this role is not formally identified as a required participant. Many of their responsibilities overlap with those of other roles, such as the IS Program Manager and Certification Agent, but they are not named explicitly in the NIACAP process.

In conclusion, the key roles mandated under NIACAP include the Certification Agent, Designated Approving Authority, IS Program Manager, and User Representative. These roles ensure comprehensive evaluation and informed authorization decisions for systems handling national security data.

Question 3:

Which penetration testing technique involves using an automated system to call a series of phone numbers in search of active modems connected to a network?

A. Demon dialing
B. Sniffing
C. Social engineering
D. Dumpster diving

Correct Answer: A

Explanation:

Demon dialing is a penetration testing technique used to locate modems connected to telephone lines within an organization’s phone number range. This method gained popularity during the era when dial-up modems were common for remote system access. Attackers, or penetration testers, would use software known as war dialers to automatically dial thousands of phone numbers sequentially, typically within the same exchange block assigned to a company. The war dialer detects which numbers respond with modem tones, indicating they are connected to a system that can potentially be accessed remotely.

Once modems are discovered, the attacker may try to connect to the system and exploit any lack of authentication, use of default credentials, or vulnerabilities in outdated remote access software. While this method is now less common due to advances in networking and security technologies, it remains a valid and historically significant technique in penetration testing—especially for environments where legacy systems are still in use.

Now, let’s evaluate the other options:

• Sniffing is unrelated to telephony. It involves capturing data packets on a network to analyze the traffic for sensitive information such as usernames, passwords, or unencrypted data. Tools like Wireshark are used for sniffing. While it’s useful in network-based penetration testing, it does not involve calling phone numbers or detecting modems.
  
  

• Social engineering refers to manipulating individuals into revealing confidential information, often through phishing emails, fake calls, or impersonation. It relies on psychological tactics, not technical methods like dialing phone numbers or scanning for modems.
  
  

• Dumpster diving is a physical reconnaissance technique that involves sifting through an organization’s trash to retrieve valuable information such as documents, passwords, or hardware. Like social engineering, it does not involve any automated dialing or scanning of phone numbers.

Therefore, among all the options listed, demon dialing is the only method that involves automated dialing of phone numbers to identify those that are connected to modems—making it the correct answer.

Question 4:

In information security and risk management, which of the following roles is commonly known as the "accreditor"?

A. Data owner
B. Chief Risk Officer
C. Chief Information Officer
D. Designated Approving Authority

Correct Answer: D

Explanation:

The role of the Designated Approving Authority (DAA), also referred to in modern terminology as the Authorizing Official (AO), is fundamental in risk management and security accreditation processes—particularly in structured frameworks such as the NIST Risk Management Framework (RMF) and military or federal security compliance models. This person is often referred to as the accreditor because they hold the authority to accept or reject the risks associated with operating an information system.

The accreditor’s responsibilities include reviewing security assessments, evaluating documentation, and determining whether residual risks are acceptable. Based on this evaluation, the DAA issues an Authorization to Operate (ATO) or denies it. Their decision is not just technical—it reflects an understanding of business impact, security controls, and organizational risk tolerance. This role serves as the final checkpoint before a system goes live, making it central to secure operations in regulated environments.

Now let’s explore why the other roles are incorrect:

• Data Owner: This role is responsible for the classification, protection, and access control of specific data sets. While data owners can define security requirements and determine who can access data, they do not have the authority to accredit a system or accept its associated risks.

• Chief Risk Officer (CRO): The CRO manages enterprise-level risk, including financial, operational, and strategic risk. They provide input on overall risk strategy but are not responsible for the specific system-level decisions required for issuing ATOs or authorizing security measures.

• Chief Information Officer (CIO): The CIO oversees the organization’s IT strategy, infrastructure, and budgeting. Although the CIO may have significant oversight over IT systems, the responsibility for authorizing systems to operate securely is usually delegated to specialized roles like the DAA, especially in regulated environments.

In conclusion, the Designated Approving Authority holds the final responsibility for system accreditation, making them synonymous with the term accreditor. This designation ensures that accountability for risk acceptance is clear and that systems do not operate without explicit approval—particularly critical in government, military, and healthcare domains.

Therefore, Option D is the correct and most accurate choice.

Question 5:

Based on the DoD 8500.2 directive, which Mission Assurance Category (MAC) level requires systems to maintain high integrity and medium availability?

A. MAC III
B. MAC IV
C. MAC I
D. MAC II

Correct Answer: D

Explanation:

The U.S. Department of Defense (DoD) once used Instruction 8500.2 to define security categorizations for its information systems, primarily under the Information Assurance (IA) framework. Though newer frameworks like the Risk Management Framework (RMF) have superseded it, the concepts introduced by 8500.2—especially Mission Assurance Categories (MACs)—still appear in exams and legacy system discussions.

The MAC levels are designed to categorize systems based on their criticality to military missions and the required levels of integrity and availability. While confidentiality is addressed separately, the MAC classification focuses on these two core attributes:

• MAC I:
  
  

• Integrity: High

• Availability: High

• These systems are mission-critical and directly support combat or emergency military operations. Any failure or downtime could severely impair mission readiness and troop safety.
  
  

• MAC II:
  
  

• Integrity: High

• Availability: Medium

• Systems in this category are essential to mission support but not as time-sensitive or life-critical as MAC I. While accuracy of data is still paramount, the availability requirements are slightly relaxed. These systems can tolerate some downtime, but not at the cost of data corruption.
  
  

• MAC III:
  
  

• Integrity: Basic

• Availability: Basic

• These are administrative or support systems. They handle routine business tasks, and while their failure may cause inconvenience, it won’t jeopardize military operations.

Let’s now analyze the choices:

• A. MAC III: Incorrect. This level only requires basic integrity and availability—too low for the "high integrity" requirement in the question.

• B. MAC IV: Invalid. There is no such category as MAC IV in DoD 8500.2. It’s a distractor.

• C. MAC I: Incorrect. While this level provides high integrity (correct), it also demands high availability—more than what the question stipulates (medium availability).

• D. MAC II: Correct. It perfectly aligns with the requirement for high integrity and medium availability, making it the appropriate MAC level.

Thus, MAC II represents systems that require accurate and reliable data for mission support but do not demand constant uptime, making it the right answer.

Question 6:

According to Michael Howard’s security code review practices, which code characteristics increase an application’s attack surface? (Select all that apply.)

A. Code developed in C, C++, or Assembly
B. Code listening on a publicly accessible network interface
C. Code that is updated frequently
D. Code accessible without authentication
E. Code that starts automatically
F. Code that operates with elevated privileges

Correct Answers: B, D, E, F

Explanation:

Michael Howard, a leading authority on secure software development, introduced several key principles in his guide “A Process for Performing Security Code Reviews.” One of his primary focuses is reducing an application’s attack surface—that is, the total number of ways an attacker could attempt to exploit a system.

The attack surface includes any entry point or externally visible code that could be manipulated. Let’s evaluate each characteristic through this lens:

• A. Code developed in C/C++/Assembly:
  Although these languages are more susceptible to low-level bugs like buffer overflows, they don’t inherently expand the attack surface. Rather, they increase internal risk due to programming complexity. So while risky, this is not a defining factor for the attack surface per Howard’s guidelines.

• B. Code listening on a globally accessible network interface:
  Yes, this contributes directly to the attack surface. If a service is available over the public internet or a global IP, it becomes an easily reachable target for attackers. Exposure like this provides an opportunity to attempt exploitation, so it's a core concern in reducing the attack surface.

• C. Code that changes frequently:
  Frequent changes may introduce bugs or regressions, but change frequency is not a structural exposure point. Howard’s definition of attack surface is about what is accessible or running, not how often it is changed. Thus, this is not a valid contributor to the attack surface.

• D. Code accessible without authentication:
  Absolutely. Any code that can be run or queried without authentication removes a crucial layer of defense. APIs or pages that don’t require login significantly increase the surface for attacks, especially from unauthenticated users.

• E. Code that runs by default:
  If a feature or service runs automatically (without user activation), it is always on—making it an ever-present exposure point. Attackers can target it even if end users are unaware of its presence. Hence, this directly increases the attack surface.

• F. Code that runs in elevated context:
  Code with admin or root privileges has more power and greater potential for damage if compromised. Any exploitable vulnerability in such code is more dangerous, making it a high-value and high-risk attack surface element.
  
  

To summarize, B, D, E, and F are all characteristics that align with Michael Howard’s definition of increased attack surface, making them the correct answers.

Question 7:

Which cryptographic service ensures that unauthorized parties are prevented from reading sensitive data transmitted over a local network?

A. Authentication
B. Integrity
C. Non-repudiation
D. Confidentiality

Correct Answer: D

Explanation:

In the realm of information security and cryptography, various services are designed to uphold different security principles—each playing a vital role in the CIA triad: Confidentiality, Integrity, and Availability. The question centers on which service ensures that unauthorized entities cannot access or interpret data, particularly within a local network environment. This concern directly pertains to confidentiality.

Confidentiality refers to the assurance that sensitive information is accessible only to those authorized to view it. In cryptographic systems, encryption is the main mechanism used to maintain confidentiality. When data is encrypted, it is transformed into ciphertext using a cryptographic algorithm and a key. Only entities possessing the correct decryption key can return the data to its readable form (plaintext). Even if the encrypted data is intercepted across a network (such as through packet sniffing), it remains unintelligible without the key, thus protecting it from unauthorized access.

Let’s evaluate the incorrect options:

• Authentication (A) confirms the identity of a user, device, or process. While it ensures that access is granted only to verified entities, it does not prevent unauthorized viewing of information in transit. Authentication precedes access but does not hide data contents.

• Integrity (B) ensures that data has not been altered during transmission. Techniques like checksums, message authentication codes (MACs), and hashing are used to detect tampering. However, integrity alone does not secure the content from being read—it only ensures it hasn't changed.

• Non-repudiation (C) involves mechanisms (such as digital signatures) that prevent parties from denying their actions—such as sending a message or performing a transaction. This supports accountability but does not prevent unauthorized viewing of data.

In contrast, Confidentiality (D) is the only service explicitly designed to prevent unauthorized disclosure. In local networks, this is especially important, as unsecured traffic can be easily intercepted with tools like Wireshark. Technologies like SSL/TLS, IPsec, WPA2/WPA3, and file-level encryption help preserve confidentiality on different levels.

In summary, when the concern is about preventing unauthorized individuals from seeing the contents of data on a network, confidentiality is the key cryptographic service involved. Thus, the correct answer is D.

Question 8:

During the planning phase of the Software Assurance Acquisition process, which of the following activities are typically conducted? (Select all that apply.)

A. Define software requirements
B. Implement change control mechanisms
C. Establish evaluation criteria and assessment plan
D. Develop an acquisition strategy

Correct Answers: A, C, D

Explanation:

The Software Assurance Acquisition process is a structured approach aimed at ensuring that software acquired by an organization—whether developed in-house or procured from vendors—meets security, quality, and functional requirements. The planning phase is the foundation of this lifecycle, setting the tone for all subsequent phases by establishing scope, strategy, and evaluation methods.

Let’s analyze each activity:

• A. Define software requirements
  This is a fundamental activity in the planning phase. The organization must outline exactly what the software must do, both functionally (e.g., user roles, processing capabilities) and non-functionally (e.g., performance, security, compliance). These requirements form the basis of later evaluations and contracts. Moreover, incorporating security-specific requirements early on ensures that risks are addressed from the start—an essential aspect of software assurance.

• B. Implement change control mechanisms
  While change control is crucial to maintaining software quality over time, it typically belongs to the execution or maintenance phases. Once software development or deployment begins, change control ensures that modifications are logged, reviewed, and approved. However, actual implementation of change control is not part of the initial planning—it may be documented or scoped during planning but is executed later. Therefore, this is not a correct planning-phase activity.

• C. Establish evaluation criteria and assessment plan
  This is a key planning task. Before selecting a software product or vendor, the organization must define how it will evaluate candidate solutions. This includes setting up metrics for cost, performance, security, vendor trustworthiness, compliance, and maintainability. The evaluation plan details the methods (e.g., penetration tests, code reviews, third-party assessments) and who will carry them out. Without this preparation, software selection could be inconsistent and risky.

• D. Develop an acquisition strategy
  This is one of the core outcomes of the planning phase. The acquisition strategy outlines how the software will be sourced—whether it’s commercial off-the-shelf (COTS), open source, or custom-developed. It also covers timelines, budget, procurement processes, risk considerations, and contract types. A clear strategy ensures alignment with business goals and security needs.

In summary, during the planning phase of software assurance acquisition, teams should: define precise software requirements (A), develop a robust acquisition strategy (D), and set clear evaluation plans (C). Change control mechanisms, while critical, are implemented later—after planning. Thus, the correct answers are A, C, and D.

Question 9:

During the requirements gathering phase of a software development project, a security professional is consulted to help identify potential risks early. 

Which of the following activities BEST demonstrates secure software practices at this stage?

A. Conducting static code analysis on early design diagrams
B. Reviewing threat models derived from use cases and abuse cases
C. Running dynamic testing on initial wireframes
D. Applying security patches to third-party libraries

Correct Answer: B

Explanation:

The requirements phase is the first formal phase in the Software Development Life Cycle (SDLC). According to the CSSLP Domain 2 – Secure Software Requirements, integrating security early is critical to reducing vulnerabilities and overall cost of remediation.

Option B is the best answer because reviewing threat models based on use cases and abuse cases is a proactive measure during the requirements gathering phase. Use cases describe how the system should behave when used correctly, while abuse cases (also known as misuse cases) help identify how attackers could exploit the system. Threat modeling helps to systematically identify security risks, prioritize mitigations, and guide secure design decisions.

Option A (static code analysis) is a good security practice but occurs during or after the coding phase, not during requirements gathering.

Option C (dynamic testing) involves executing the application to find vulnerabilities at runtime. This is typically done during testing, not at the requirements phase.

Option D (applying patches) is part of maintenance or secure configuration, not a relevant activity for requirement gathering.

By conducting threat modeling during the requirements phase, development teams gain visibility into security threats early, allowing them to write more secure code from the start. This practice aligns with “shift-left security”—incorporating security as early as possible in the lifecycle.

Thus, Option B aligns perfectly with secure SDLC principles and the CSSLP philosophy of early risk mitigation.

Question 10:

A development team integrates a new third-party payment API into their e-commerce platform. As part of secure software lifecycle practices, which action is MOST critical to ensure the API does not introduce security vulnerabilities?

A. Verifying the vendor’s business reputation and longevity
B. Reviewing the API documentation for performance specifications
C. Conducting a security assessment of the API before integration
D. Testing the API only after it has been deployed to production

Correct Answer: C

Explanation:

Third-party components, including APIs, are common in modern software development. However, they can introduce vulnerabilities if not properly vetted. This question touches on CSSLP Domain 6 – Secure Software Testing and Domain 5 – Secure Software Design, both of which emphasize validating external components.

Option C is the correct answer because conducting a security assessment before integration is critical to ensure that the API complies with security standards, does not have known vulnerabilities, and won’t introduce risks into your system. This includes checking for authentication mechanisms, encryption of sensitive data, rate limiting, and input validation.

Option A (verifying the vendor’s reputation) is useful from a procurement or business continuity perspective but does not guarantee technical security.

Option B (reviewing API documentation) helps with understanding functionality and usage but doesn't validate the security posture of the API.

Option D (testing after deployment) is too late. Vulnerabilities should be identified before production, aligning with the principle of “fail early and fail fast” in secure development.

The integration of third-party components poses risks such as supply chain attacks, insecure endpoints, and unauthorized access if not properly controlled. By performing a security assessment—which may include static analysis, dynamic analysis, fuzz testing, or reviewing security certifications—you significantly reduce the risk of introducing vulnerabilities.

This question reflects the CSSLP’s emphasis on proactive and preventive measures to uphold security across the software lifecycle, especially when incorporating external software dependencies.