CS0-003 CompTIA CyberSecurity Analyst CySA+ Certification Exam Free Practice Exam Questions (2026 Updated)

Comprehensive and Detailed Step-by-Step Explanation:The logs indicate that the OWASP DirBuster tool is being used. This tool is designed for directory brute-forcing to find hidden files or directories on a web server, which aligns with reconnaissance activities. The series of GET and HEAD requests further confirm directory and file enumeration attempts.

Wiresharkis apacket capture and analysis toolthat allows analysts to inspect network traffic and detectcleartext credentialssent over protocols like HTTP, FTP, and Telnet​.

Option A (OpenVAS)is avulnerability scanner, not a network analysis tool.

Option B (Angry IP Scanner)identifiesactive hosts, but does not analyze packet contents.

Option D (Maltego)is used forOSINT and network reconnaissance, not packet inspection.

Thus,C (Wireshark) is the correct answer, as itcaptures and analyzes network packets to identify unencrypted passwords​.

The MTTD (Mean Time To Detect) is calculated by averaging the time elapsed in detecting incidents. From the given data: (180+150+170+140)/4 = 160 minutes. This is the correct answer according to the CompTIA CySA+ CS0-003 Certification Study Guide1, Chapter 4, page 161. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 4, page 153; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 4, page 161.

tcpdump is a command-line tool that can capture and analyze network packets from a given interface or file. The -n option prevents tcpdump from resolving hostnames, which can speed up the analysis. The -r option reads packets from a file, in this case packets.pcap. The host [IP address] filter specifies that tcpdump should only display packets that have the given IP address as either the source or thedestination. This command can help the security analyst detect connections to a suspicious IP address by collecting the packet captures from the gateway. Official References:

https://partners.comptia.org/docs/default-source/resources/comptia-cysa-cs0-002-exam-objectives

https://www.techtarget.com/searchsecurity/quiz/Sample-CompTIA-CySA-test-questions-with-answers

https://www.reddit.com/r/CompTIA/comments/tmxx84/passed_cysa_heres_my_experience_and_how_i_studied/

Passive scanning is a method of vulnerability identification that does not send any packets or probes to the target devices, but rather observes and analyzes the network traffic passively. Passive scanning can minimize the risk of OT/ICS devices malfunctioning due to the vulnerability identification process, as it does not interfere with the normal operation of the devices or cause any network disruption. Passive scanning can also detect vulnerabilities that active scanning may miss, such as misconfigured devices, rogue devices or unauthorized traffic. Official References:

https://partners.comptia.org/docs/default-source/resources/comptia-cysa-cs0-002-exam-objectives

https://www.comptia.org/blog/the-new-comptia-cybersecurity-analyst-your-questions-answered

https://www.comptia.org/certifications/cybersecurity-analyst

The correct answers for key factors in the change management process to reduce the impact of system failures are:

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.

D. 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.

F. 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:

A. 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.

B. 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.

C. 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.

E. 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.

Defense evasion is the technique of avoiding detection or prevention by security tools or mechanisms. In this case, the freeware program is likely a malware that generates random DNS queries to communicate with a command and control server or exfiltrate data. The command Add-MpPreference -ExclusionPath '%Program Filest\ksysconfig' is used to add an exclusion path to Windows Defender, which is a built-in antivirus software, to prevent it from scanning the malware folder. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 5, page 204; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 5, page 212. pr

Comprehensive Detailed Explanation:The nmap scan results show that Telnet (port 23) is open. Telnet transmits data, including credentials, in plaintext, which is insecure and should be disabled to enhance security. Here’s an explanation of each option:

A. Disable all protocols that do not use encryption

Explanation: Disabling unencrypted protocols (such as Telnet) reduces exposure to man-in-the-middle (MITM) attacks and credential sniffing. Telnet should be replaced with a secure protocol like SSH, which provides encryption for transmitted data.

B. Configure client certificates for domain services

Explanation: While client certificates enhance authentication security, they are more relevant to services like LDAP over SSL (port 636), which is already secure. This would not address the Telnet vulnerability.

C. Ensure that this system is behind a NGFW

Explanation: A Next-Generation Firewall (NGFW) provides enhanced network security, but it may not mitigate the risks of unencrypted protocols if they are allowed internally.

D. Deploy a publicly trusted root CA for secure websites

Explanation: Public root CAs are used for website authentication and encryption, relevant only if this system is hosting a publicly accessible HTTPS service. It would not impact Telnet security.

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.

Cloud-specific misconfigurations are security issues that arise from improper or inadequate configuration of cloud resources, such as storage buckets, databases, virtual machines, or containers. Cloud-specific misconfigurations may not be detected by the current scanners that are designed for on-premises environments, as they may not have the visibility or access to the cloud resources or the cloud provider’s APIs. Therefore, one of the implications that should be considered on the new hybrid environment is that cloud-specific misconfigurations may not be detected by the current scanners.

Wireshark is a network protocol analyzer that allows analysts to capture and inspect data packets traveling through a network. This makes it ideal for investigating unusual network activity, as it provides detailed insights into the nature and content of network traffic. In this case, Wireshark can help identify potentially malicious packets and understand the nature of the observed traffic. Options A (WAF) and C (EDR) are primarily used for monitoring and protecting web applications and endpoints, respectively, and Nmap (D) is typically used for network discovery and mapping, not detailed traffic analysis. According to CompTIA CySA+, packet analysis tools like Wireshark are invaluable for deep-dive investigations into network anomalies.

The most likely reason to include lessons learned in an after-action report is to identify areas of improvement in the incident response process. The lessons learned process is a way of reviewing and evaluating the incident response activities and outcomes, as well as identifying and documenting any strengths, weaknesses, gaps, or best practices. Identifying areas of improvement in the incident response process can help enhance the security posture, readiness, or capability of the organization for future incidents, as well as provide feedback or recommendations on how to address any issues or challenges.

Mean Time to Detect (MTTD) is the most appropriate Key Performance Indicator (KPI) to monitor the effectiveness of an incident response reporting and communication program among the choices provided.

Why B is correct: The primary goal of an "incident reporting" program (whether automated by tools or reported by users/staff) is to alert the security team to an issue as quickly as possible. MTTD measures the average time it takes for an organization to identify (detect and report) an incident after it has occurred. A lower MTTD directly indicates that the reporting mechanisms and communication channels from the source to the analysts are operating effectively.

Why A is incorrect: Incident volume measures the quantity of incidents, which reflects the threat landscape or workload rather than the effectiveness of the response program itself. While an increase in user-reported volume can indicate better awareness, MTTD is the standard performance metric for the process.

Why C is incorrect: Average time to patch is a KPI for Vulnerability Management, not Incident Response reporting.

Why D is incorrect: Remediated incidents refers to the volume of resolved issues (Response/Recovery phase) and does not specifically measure the speed or quality of the reporting and communication (detection) phase.

In Domain 4 (Reporting and Communication) and Domain 1 (Security Operations), CompTIA emphasizes the use of time-based metrics to evaluate process maturity.

MTTD (Mean Time to Detect): Measures "dwell time" and the efficiency of the Detection & Reporting phase.

MTTR (Mean Time to Respond): Measures the efficiency of the Response & Recovery phase.

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ThePHP script allows remote users to execute system commands via the system() function, meaning an attacker can send arbitrary commands to the server​.

Option A (Cross-site scripting - XSS)is incorrect because this script does not inject JavaScript into a webpage.

Option B (Reverse shell)is possible if an attacker sends a crafted command, but the script itself is more of a general backdoor than a dedicated reverse shell.

Option D (Logic bomb)is incorrect because a logic bomb is typicallytriggered by a specific event or daterather than executing arbitrary commands on demand.

Thus,C (Backdoor attempt) is the best answer, as this scriptgrants unauthorized remote command execution.

The lessons learned process is the final stage of the incident management life cycle, where the incident team reviews the incident and evaluates the effectiveness of the response and the plans in place. The lessons learned report should include the who-what-when information and any recommendations for improvement123 References: 1: What is incident management? Steps, tips, and best practices 2: 5 Steps of the Incident Management Lifecycle | RSI Security 3: Navigating the Incident Response Life Cycle: A Comprehensive Guide

Outdated librariesin a legacy web applicationintroduce security vulnerabilities, as theylack modern patchesandcontain known exploits​.

Option A (Misconfigured WAF)can contribute to security issues but is notinherent to legacy applications.

Option B (Data integrity failure)is apotential impactbut not a direct cause of recurring incidents.

Option D (Insufficient logging)affects detection, but theroot causeisinsecure, outdated components.

Thus,C (Outdated libraries) is the correct answer, aslegacy applications frequently suffer from unpatched vulnerabilities​.

Under the terms of PCI DSS, an organization that has experienced a breach of customer transactions should report the breach to the card issuer. The card issuer is the financial institution that issues the payment cards to the customers and that is responsible for authorizing and processing the transactions. The card issuer may have specific reporting requirements and procedures for the organization to follow in the event of a breach. The organization should also notify other parties that may be affected by the breach, such as customers, law enforcement, or regulators, depending on the nature and scope of the breach. Official References: https://www.pcisecuritystandards.org/

An SLA, or Service Level Agreement, is a contract between a service provider and its customers that documents what services the provider will furnish and defines the service standards the provider is obligated to meet. In the scenario described, the missed incident response deadline is a clear indicator of an SLA violation. An SLA usually outlines the metrics by which service is measured as well as remedies or penalties should agreed-upon service levels not be achieved. Unlike a KPI (Key Performance Indicator) which is a quantifiable measure used to evaluate the success of an organization, employee, etc., in meeting objectives for performance, or an MOU (Memorandum of Understanding) which is a formal agreement between two or more parties, an SLA is focused on the performance and quality metrics applicable to the service provided. SLO (Service Level Objective) is related and often part of an SLA, representing the specific measurable characteristics of the SLA such as availability, throughput, frequency, response time, or quality.

The output shows that port 80 is open and running an HTTP service, indicating that the host could potentially be vulnerable to web-based attacks. The other options are not relevant for this purpose: the host is responsive to the ICMP request, as shown by the “Host is up” message; the host is not running a mail server, as there is no SMTP or POP3 service detected; the host is not allowing unsecured FTP connections, as there is no FTP service detected.References: According to the CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition123, one of the objectives for the exam is to “use appropriate tools and methods to manage, prioritize and respond to attacks and vulnerabilities”. The book also covers the usage and syntax of nmap, a popular network scanning tool, in chapter 5. Specifically, it explains the meaning and function of each option in nmap, such as “-sV” for version detection2, page 195. Therefore, this is a reliable source to verify the answer to the question.