CompTIA CompTIA Certifications CS0-003 Questions & Answers

• Question 121:

  During a recent site survey. an analyst discovered a rogue wireless access point on the network. Which of the following actions should be taken first to protect the network while preserving evidence?

  A. Run a packet sniffer to monitor traffic to and from the access point.

  B. Connect to the access point and examine its log files.

  C. Identify who is connected to the access point and attempt to find the attacker.

  D. Disconnect the access point from the network

  Correct Answer: D

  A rogue access point is a wireless access point that has been installed on a network without the authorization or knowledge of the network administrator. A rogue access point can pose a serious security risk, as it can allow unauthorized users to access the network, intercept network traffic, or launch attacks against the network or its devices1234. The first action that should be taken to protect the network while preserving evidence is to disconnect the rogue access point from the network. This will prevent any further damage or compromise of the network by blocking the access point from communicating with other devices or users. Disconnecting the rogue access point will also preserve its state and configuration, which can be useful for forensic analysis and investigation. Disconnecting the rogue access point can be done physically by unplugging it from the network port or wirelessly by disabling its radio frequency5. The other options are not the best actions to take first, as they may not protect the network or preserve evidence effectively. Option A is not the best action to take first, as running a packet sniffer to monitor traffic to and from the access point may not stop the rogue access point from causing harm to the network. A packet sniffer is a tool that captures and analyzes network packets, which are units of data that travel across a network. A packet sniffer can be useful for identifying and troubleshooting network problems, but it may not be able to prevent or block malicious traffic from a rogue access point. Moreover, running a packet sniffer may require additional time and resources, which could delay the response and mitigation of the incident5. Option B is not the best action to take first, as connecting to the access point and examining its log files may not protect the network or preserve evidence. Connecting to the access point may expose the analyst's device or credentials to potential attacks or compromise by the rogue access point. Examining its log files may provide some information about the origin and activity of the rogue access point, but it may also alter or delete some evidence that could be useful for forensic analysis and investigation. Furthermore, connecting to the access point and examining its log files may not prevent or stop the rogue access point from continuing to harm the network5. Option C is not the best action to take first, as identifying who is connected to the access point and attempting to find the attacker may not protect the network or preserve evidence. Identifying who is connected to the access point may require additional tools or techniques, such as scanning for wireless devices or analyzing network traffic, which could take time and resources away from responding and mitigating the incident. Attempting to find the attacker may also be difficult or impossible, as the attacker may use various methods to hide their identity or location, such as encryption, spoofing, or proxy servers. Moreover, identifying who is connected to the access point and attempting to find the attacker may not prevent or stop the rogue access point from causing further damage or compromise to the network5. References: 1 CompTIA Cybersecurity Analyst (CySA+) Certification Exam Objectives 2 Cybersecurity Analyst+ - CompTIA 3 CompTIA CySA+ CS0-002 Certification Study Guide 4 CertMaster Learn for CySA+ Training - CompTIA 5 How to Protect Against Rogue Access Points on Wi-Fi - Byos 6 Wireless Access Point Protection: 5 Steps to Find Rogue Wi-Fi Networks ... 7 Rogue Access Point - Techopedia 8 Rogue access point - Wikipedia 9 What is a Rogue Access Point (Rogue AP)? - Contextual Security

• Question 122:

  A company brings in a consultant to make improvements to its website. After the consultant leaves. a web developer notices unusual activity on the website and submits a suspicious file containing the following code to the security team: Which of the following did the consultant do?

  

  A. Implanted a backdoor

  B. Implemented privilege escalation

  C. Implemented clickjacking

  D. Patched the web server

  Correct Answer: A

  A backdoor is a method that allows an unauthorized user to access a system or network without the permission or knowledge of the owner. A backdoor can be installed by exploiting a software vulnerability, by using malware, or by physically modifying the hardware or firmware of the device. A backdoor can be used for various malicious purposes, such as stealing data, installing malware, executing commands, or taking control of the system. In this case, the consultant implanted a backdoor in the website by using an HTML and PHP code snippet that displays an image of a shutdown button and an alert message that says "Exit". However, the code also echoes the remote address of the server, which means that it sends the IP address of the visitor to the attacker. This way, the attacker can identify and target the visitors of the website and use their IP addresses to launch further attacks or gain access to their devices. The code snippet is an example of a clickjacking attack, which is a type of interface-based attack that tricks a user into clicking on a hidden or disguised element on a webpage. However, clickjacking is not the main goal of the consultant, but rather a means to implant the backdoor. Therefore, option C is incorrect. Option B is also incorrect because privilege escalation is an attack technique that allows an attacker to gain higher or more permissions than they are supposed to have on a system or network. Privilege escalation can be achieved by exploiting a software vulnerability, by using malware, or by abusing misconfigurations or weak access controls. However, there is no evidence that the consultant implemented privilege escalation on the website or gained any elevated privileges. Option D is also incorrect because patching is a process of applying updates to software to fix errors, improve performance, or enhance security. Patching can prevent or mitigate various types of attacks, such as exploits, malware infections, or denial-of-service attacks. However, there is no indication that the consultant patched the web server or improved its security in any way. References: 1 What Is a Backdoor and How to Prevent Backdoor Attacks (2023) 2 What is Clickjacking? Tutorial and Examples | Web Security Academy 3 What Is Privilege Escalation and How It Relates to Web Security | Acunetix 4 What Is Patching? | Best Practices For Patch Management - cWatch Blog

• Question 123:

  A cybersecurity analyst is recording the following details

  1.

  ID

  2.

  Name

  3.

  Description

  4.

  Classification of information

  5.

  Responsible party

  In which of the following documents is the analyst recording this information?

  A. Risk register

  B. Change control documentation

  C. Incident response playbook

  D. Incident response plan

  Correct Answer: A

  A risk register typically contains details like ID, name, description, classification of information, and responsible party. It's used for tracking identified risks and managing them.Recording details like ID, Name, Description, Classification of information, and Responsible party is typically done in a Risk Register. This document is used to identify, assess, manage, and monitor risks within an organization. It's not directly related to incident response or change control documentation.

• Question 124:

  A software developer has been deploying web applications with common security risks to include insufficient logging capabilities. Which of the following actions would be most effective to reduce risks associated with the application development?

  A. Perform static analyses using an integrated development environment.

  B. Deploy compensating controls into the environment.

  C. Implement server-side logging and automatic updates.

  D. Conduct regular code reviews using OWASP best practices.

  Correct Answer: D

  Conducting regular code reviews using OWASP best practices is the most effective action to reduce risks associated with the application development. Code reviews are a systematic examination of the source code of an application to detect and fix errors, vulnerabilities, and weaknesses that may compromise the security, functionality, or performance of the application. Code reviews can help to improve the quality and security of the code, as well as to identify and remediate common security risks, such as insufficient logging capabilities. OWASP (Open Web Application Security Project) is a global nonprofit organization that provides free and open resources, tools, standards, and best practices for web application security. OWASP best practices for logging include following a common logging format and approach, logging relevant security events and data, protecting log data from unauthorized access or modification, and using log analysis and monitoring tools to detect and respond to security incidents. By following OWASP best practices for logging, developers can ensure that their web applications have sufficient and effective logging capabilities that can help to prevent, detect, and mitigate security threats. References: OWASP Logging Cheat Sheet, OWASP Logging Guide, C9: Implement Security Logging and Monitoring - OWASP Foundation

• Question 125:

  AXSS vulnerability was reported on one of the non-sensitive/non-mission-critical public websites of a company. The security department confirmed the finding and needs to provide a recommendation to the application owner. Which of the following recommendations will best prevent this vulnerability from being exploited? (Select two).

  A. Implement an IPS in front of the web server.

  B. Enable MFA on the website.

  C. Take the website offline until it is patched.

  D. Implement a compensating control in the source code.

  E. Configure TLS v1.3 on the website.

  F. Fix the vulnerability using a virtual patch at the WAF.

  Correct Answer: DF

  The best recommendations to prevent an XSS vulnerability from being exploited are to implement a compensating control in the source code and to fix the vulnerability using a virtual patch at the WAF. A compensating control is a technique

  that mitigates the risk of a vulnerability by adding additional security measures, such as input validation, output encoding, or HTML sanitization. A virtual patch is a rule that blocks or modifies malicious requests or responses at the WAF level,

  without modifying the application code. These recommendations are effective, efficient, and less disruptive than the other options. References: CompTIA CySA+ Study Guide: S0-003, 3rd Edition, Chapter 4:

  Security Operations and Monitoring, page 156; Cross Site Scripting Prevention Cheat Sheet, Section: XSS Defense Philosophy.

• Question 126:

  A SOC manager is establishing a reporting process to manage vulnerabilities. Which of the following would be the best solution to identify potential loss incurred by an issue?

  A. Trends

  B. Risk score

  C. Mitigation

  D. Prioritization

  Correct Answer: B

  A risk score is a numerical value that represents the potential impact and likelihood of a vulnerability being exploited. It can help to identify the potential loss incurred by an issue and prioritize remediation efforts accordingly. https://www.comptia.org/training/books/cysa-cs0-003-study-guide

• Question 127:

  Which of the following most accurately describes the Cyber Kill Chain methodology?

  A. It is used to correlate events to ascertain the TTPs of an attacker.

  B. It is used to ascertain lateral movements of an attacker, enabling the process to be stopped.

  C. It provides a clear model of how an attacker generally operates during an intrusion and the actions to take at each stage

  D. It outlines a clear path for determining the relationships between the attacker, the technology used, and the target

  Correct Answer: C

  The Cyber Kill Chain methodology provides a clear model of how an attacker generally operates during an intrusion and the actions to take at each stage. It is divided into seven stages: reconnaissance, weaponization, delivery, exploitation,

  installation, command and control, and actions on objectives. It helps network defenders understand and prevent cyberattacks by identifying the attacker's objectives and tactics. References:

  The Cyber Kill Chain: The Seven Steps of a Cyberattack

• Question 128:

  The management team requests monthly KPI reports on the company's cybersecurity program. Which of the following KPIs would identify how long a security threat goes unnoticed in the environment?

  A. Employee turnover

  B. Intrusion attempts

  C. Mean time to detect

  D. Level of preparedness

  Correct Answer: C

  Mean time to detect (MTTD) is a metric that measures the average time it takes for an organization to discover or detect an incident. It is a key performance indicator in incident management and a measure of incident response capabilities. A low MTTD indicates that the organization can quickly identify security threats and minimize their impact12. References: What Is MTTD (Mean Time to Detect)? A Detailed Explanation, Introduction to MTTD: Mean Time to Detect

• Question 129:

  While performing a dynamic analysis of a malicious file, a security analyst notices the memory address changes every time the process runs. Which of the following controls is most likely preventing the analyst from finding the proper memory address of the piece of malicious code?

  A. Address space layout randomization

  B. Data execution prevention

  C. Stack canary

  D. Code obfuscation

  Correct Answer: A

  Address space layout randomization (ASLR) is a security control that randomizes the memory address space of a process, making it harder for an attacker to exploit memory- based vulnerabilities, such as buffer overflows1. ASLR can also prevent a security analyst from finding the proper memory address of a piece of malicious code, as the memory address changes every time the process runs2. The other options are not the best explanations for why the memory address changes every time the process runs. Data execution prevention (B) is a security control that prevents code from being executed in certain memory regions, such as the stack or the heap3. Stack canary ?is a security technique that places a random value on the stack before a function's return address, to detect and prevent stack buffer overflows. Code obfuscation (D) is a technique that modifies the source code or binary of a program to make it more difficult to understand or reverse engineer. These techniques do not affect the memory address space of a process, but rather the execution or analysis of the code.

• Question 130:

  During a security test, a security analyst found a critical application with a buffer overflow vulnerability. Which of the following would be best to mitigate the vulnerability at the application level?

  A. Perform OS hardening.

  B. Implement input validation.

  C. Update third-party dependencies.

  D. Configure address space layout randomization.

  Correct Answer: B

  Implementing input validation is the best way to mitigate the buffer overflow vulnerability at the application level. 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 application from being compromised12. References: How to detect, prevent, and mitigate buffer overflow attacks - Synopsys, How to mitigate buffer overflow vulnerabilities | Infosec