CompTIA CS0-003 Online Practice Questions and Exam Preparation

CompTIA CS0-003 Online Questions & Answers

• Question 511:

  A manufacturer has hired a third-party consultant to assess the security of an OT network that includes both fragile and legacy equipment.

  Which of the following must be considered to ensure the consultant does no harm to operations?

  A. Employing Nmap Scripting Engine scanning techniques
  B. Preserving the state of PLC ladder logic prior to scanning
  C. Using passive instead of active vulnerability scans
  D. Running scans during off-peak manufacturing hours
  C. Using passive instead of active vulnerability scans

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  Explanation

  In environments with fragile and legacy equipment, passive scanning is preferred to prevent any potential disruptions that active scanning might cause.

  When assessing the security of an Operational Technology (OT) network, especially one with fragile and legacy equipment, it's crucial to use passive instead of active vulnerability scans. Active scanning can sometimes disrupt the operation of sensitive or older equipment. Passive scanning listens to network traffic without sending probing requests, thus minimizing the risk of disruption.

• Question 512:

  A security analyst needs to identify services in a small, critical infrastructure ICS network. Many components in the network are likely to break if they receive malformed or unusually large requests.

  Which of the following is the safest method to use when identifying service versions?

  A. Use nmap -sV to identify all assets on the network.
  B. Use Burp Suite to conduct service identification.
  C. Use nc to manually perform banner grabbing.
  D. Use Nessus with restricted concurrent connections.
  C. Use nc to manually perform banner grabbing.

• Question 513:

  A security analyst is validating a particular finding that was reported in a web application vulnerability scan to make sure it is not a false positive. The security analyst uses the snippet below:

  

  Which of the following vulnerability types is the security analyst validating?

  A. Directory traversal
  B. XSS
  C. XXE
  D. SSRF
  C. XXE

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  Explanation

  XML external entity injection (also known as XXE) is a web security vulnerability that allows an attacker to interfere with an application's processing of XML data. It often allows an attacker to view files on the application server filesystem, and to interact with any back-end or external systems that the application itself can access.

  In some situations, an attacker can escalate an XXE attack to compromise the underlying server or other back-end infrastructure, by leveraging the XXE vulnerability to perform server-side request forgery (SSRF) attacks.

  References:

  https://portswigger.net/web-security/xxehttps://portswigger.net/web-security/xxe/xml-entitieshttps://owasp.org/www-community/vulnerabilities/XML_External_Entity_(XXE)_Processing

• Question 514:

  Which of the following stakeholders are most likely to receive a vulnerability scan report? (Select two).

  A. Executive management
  B. Law enforcement
  C. Marketing
  D. Legal
  E. Product owner
  F. Systems admininstration
  A. Executive management
  F. Systems admininstration

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  Explanation

  Executive management and systems administration are the most likely stakeholders to receive a vulnerability scan report because they are responsible for overseeing the security posture and remediation efforts of the organization. Law enforcement, marketing, legal, and product owner are less likely to be involved in the vulnerability management process or need access to the scan results.

  References:

  Cybersecurity Analyst+ - CompTIA, How To Write a Vulnerability Assessment Report | EC-Council, Driving Stakeholder Alignment in Vulnerability Management - LogicGate

• Question 515:

  The DevSecOps team is remediating a Server-Side Request Forgery (SSRF) issue on the company's public-facing website.

  Which of the following is the best mitigation technique to address this issue?

  A. Place a Web Application Firewall (WAF) in front of the web server.
  B. Install a Cloud Access Security Broker (CASB) in front of the web server.
  C. Put a forward proxy in front of the web server.
  D. Implement MFA in front of the web server.
  A. Place a Web Application Firewall (WAF) in front of the web server.

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  Explanation

  Server-Side Request Forgery (SSRF) occurs when an attacker manipulates a web server to make unauthorized internal or external requests, often to access internal resources or exfiltrate data.

  A Web Application Firewall (WAF) is the best mitigation because it:

  Why Not Other Options?

  B (CASB) Used for cloud access control, not effective against SSRF. C (Forward Proxy) Helps with outbound traffic control, but SSRF involves incoming requests. D (MFA) Helps with authentication but does NOT prevent SSRF attacks.

  References:

  CompTIA CySA+ CS0-003, Chapter 6: "Application Security and Secure Coding," Section: "Preventing SSRF and Web Exploits."

• Question 516:

  A penetration tester submitted data to a form in a web application, which enabled the penetration tester to retrieve user credentials.

  Which of the following should be recommended for remediation of this application vulnerability?

  A. Implementing multifactor authentication on the server OS
  B. Hashing user passwords on the web application
  C. Performing input validation before allowing submission
  D. Segmenting the network between the users and the web server
  C. Performing input validation before allowing submission

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  Explanation

  Performing input validation before allowing submission is the best recommendation for remediation of this application vulnerability. Input validation is a technique that checks the data entered by users or attackers against a set of rules or constraints, such as data type, length, format, or range. Input validation can prevent common web application attacks such as SQL injection, cross-site scripting (XSS), or command injection, which exploit the lack of input validation to execute malicious code or commands on the server or the client side. By validating the input before allowing submission, the web application can reject or sanitize any malicious or unexpected input, and protect the user credentials and other sensitive data from being compromised 12.

  References:

  Input Validation - OWASP, 4 Most Common Application Vulnerabilities and Possible Remediation

• Question 517:

  A security analyst has identified outgoing network traffic leaving the enterprise at odd times. The traffic appears to pivot across network segments and target domain servers. The traffic is then routed to a geographic location to which the company has no association.

  Which of the following best describes this type of threat?

  A. Hacktivist
  B. Zombie
  C. Insider threat
  D. Nation-state actor
  D. Nation-state actor

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  Explanation

  The described behavior (pivoting across network segments, targeting domain servers, and exfiltrating data to an unknown location) is characteristic of an advanced persistent threat (APT), often linked to nation-state actors. Option A (Hacktivist) attackers typically engage in defacements or disruption rather than stealthy exfiltration.

  Option B (Zombie) refers to compromised hosts in a botnet, but botnets do not usually pivot across networks.

  Option C (Insider threat) could involve unauthorized access, but the traffic pattern suggests an external attacker with lateral movement techniques. Thus, D is the correct answer, as nation-state actors often use sophisticated tactics, including data exfiltration and network pivoting.

• Question 518:

  Which of the following best describes the benefit of implementing a PAM solution?

  A. Measuring and validating the integrity of the database
  B. Controlling and monitoring the use of administrative accounts
  C. Storing and protecting PKI certificate private keys
  D. Configuring and enforcing password complexity requirements
  B. Controlling and monitoring the use of administrative accounts

• Question 519:

  An organization has established a formal change management process after experiencing several critical system failures over the past year.

  Which of the following are key factors that the change management process will include in order to reduce the impact of system failures?

  (Select two).

  A. Ensure users the document system recovery plan prior to deployment.
  B. Perform a full system-level backup following the change.
  C. Leverage an audit tool to identify changes that are being made.
  D. Identify assets with dependence that could be impacted by the change.
  E. Require diagrams to be completed for all critical systems.
  F. Ensure that all assets are properly listed in the inventory management system.
  D. Identify assets with dependence that could be impacted by the change.
  F. Ensure that all assets are properly listed in the inventory management system.

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  Explanation

  The correct answers for key factors in the change management process to reduce the impact of system failures are: Identify assets with dependence that could be impacted by the change: This is crucial in change management because understanding the interdependencies among assets can help anticipate and mitigate the potential cascading effects of a change. By identifying these dependencies, the organization can plan more effectively for changes and minimize the risk of unintended consequences that could lead to system failures.

  Ensure that all assets are properly listed in the inventory management system: Maintaining an accurate and comprehensive inventory of assets is fundamental in change management. Knowing exactly what assets the organization possesses and their characteristics allows for better planning and impact analysis when changes are made. This ensures that no critical component is overlooked during the change process, reducing the risk of failures due to incomplete information.

  Other Options:

  Ensure users document system recovery plan prior to deployment: While documenting a system recovery plan is important, it's more related to disaster recovery and business continuity planning than directly reducing the impact of system failures due to changes.

  Perform a full system-level backup following the change: While backups are essential, they are generally a reactive measure to recover from a failure, rather than a proactive measure to reduce the impact of system failures in the first place.

  Leverage an audit tool to identify changes that are being made: While using an audit tool is helpful for tracking changes and ensuring compliance, it is not directly linked to reducing the impact of system failures due to changes. Require diagrams to be completed for all critical systems: While having diagrams of critical systems is useful for understanding and managing them, it is not a direct method for reducing the impact of system failures due to changes.Diagrams are more about documentation and understanding rather than proactive change management.

• Question 520:

  A security analyst discovers the company's website is vulnerable to cross-site scripting.

  Which of the following solutions will best remedy the vulnerability?

  A. Prepared statements
  B. Server-side input validation
  C. Client-side input encoding
  D. Disabled JavaScript filtering
  B. Server-side input validation

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  Explanation

  Server-side input validation is a solution that can prevent cross-site scripting (XSS) vulnerabilities by checking and filtering any user input that is sent to the server before rendering it on a web page. Server-side input validation can help to ensure that the user input conforms to the expected format, length and type, and does not contain any malicious characters or syntax that may alter the logic or behavior of the web page. Server-side input validation can also reject or sanitize any input that does not meet the validation criteria .

  https://portswigger.net/web-security/cross-site-scripting/preventing