CS0-003 CompTIA CyberSecurity Analyst CySA+ Certification Exam Free Practice Exam Questions (2025 Updated)

The best action for the incident response team to recommend in this scenario is to perform no action until HR or legal counsel advises on next steps. This action can help avoid any potential legal or ethical issues, such as violating employee privacy rights, contractual obligations, or organizational policies. This action can also help ensure that any evidence or information collected from the employee’s system or network is admissible and valid in case of any legal action or dispute. The incident response team should consult with HR or legal counsel before taking any action that may affect the employee’s system or network.

Rolling out a CDN is the best control to mitigate the Layer 4 DDoS attacks against the company website. A CDN is a Content Delivery Network, which is a system of distributed servers that deliver web content to users based on their geographic location, the origin of the web page, and the content delivery server. A CDN can help protect against Layer 4 DDoS attacks, which are volumetric attacks that aim to exhaust the network bandwidth or resources of the target website by sending a large amount of traffic, such as SYN floods, UDP floods, or ICMP floods. A CDN can mitigate these attacks by distributing the traffic across multiple servers, caching the web content closer to the users, filtering out malicious or unwanted traffic, and providing scalability and redundancy for the website12. References: How to Stop a DDoS Attack: Mitigation Steps for Each OSI Layer, Application layer DDoS attack | Cloudflare

A lessons-learned review is a process of evaluating the effectiveness and efficiency of the incident response plan after an incident or an exercise. The purpose of the review is to identify the strengths and weaknesses of the incident response plan, and to update it accordingly to improve the future performance and resilience of the organization. Therefore, the incident response plan should be updated after a lessons-learned review.

An incident manager should work with the legal and public relations entities to ensure correct processes are adhered to when communicating incident reporting to the general public, as a best practice. The legal entity can provide guidance on the legal implications and obligations of disclosing the incident, such as compliance with data protection laws, contractual obligations, and liability issues. The public relations entity can help craft the appropriate message and tone for the public communication, as well as manage the reputation and image of the organization in the aftermath of the incident. These two entities can help the incident manager balance the need for transparency and accountability with the need for confidentiality and security12. References: Incident Communication Templates, Incident Management: Processes, Best Practices & Tools - Atlassian

To improve the detection of known attacks and behavioralIndicators of Compromise (IoCs), the best approach is tointegrate with an open-source threat intelligence feed. Threat intelligence feeds provide up-to-date information on known malicious IPs, domains, file hashes, and behavioral patterns that attackers use​.

Option A (randomly generating and storing hash values)is impractical, as there are an infinite number of possible files.

Option B (alerting on any system change)would lead to excessive noise and false positives, making the system difficult to manage.

Option D (manually adding signatures)is useful but is not scalable or as timely as an external intelligence feed​.

Thus, the correct answer isC, as integrating an open-source threat intelligence feed enhances the SIEM’s ability to detect and respond to real-world threats​.

The system “blane” with the vulnerability name “snakedoctor” should be prioritized for patching as it has a network attack vector (AV:N), low attack complexity (AC:L), and high availability (A:H). These metrics indicate that it would be relatively easy to exploit this vulnerability over the internet, and the system is highly available. References: According to the CVSS v3.1 Specification Document, the exploitability metrics for CVSS are Attack Vector, Attack Complexity, Privileges Required, User Interaction, and Scope. These metrics measure how the vulnerability is accessed, the complexity of the attack, and the level of interaction and privileges required to exploit the vulnerability. The image shows a table with the values of these metrics for each system and vulnerability. Based on these values, the system “blane” has the highest exploitability score, as it has the most favorable conditions for an attacker. The other systems have either a lower attack vector, higher attack complexity, or lower availability, which make them less exploitable. Therefore, the system “blane” should be patched first.

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.

A HTTP/404 error code means that the requested page or resource was not found on the web server. This could be caused by various reasons, such as incorrect URLs, moved or deleted pages, missing assets, or server misconfigurations123. The analyst should first identify the source of the requests and examine the related activity to determine if they are legitimate or malicious, and what actions need to be taken to resolve the issue. The other options are either premature or irrelevant without further investigation. References: 1: 404 Page Not Found Error: What It Is and How to Fix It 2: 404 Error Code: What Causes Them and How To Fix It 3: About 404 errors and how to Troubleshoot it?

Weaponization is the stage of the Cyber Kill Chain where the attacker creates or modifies a malicious payload to use against a target. In this case, the disgruntled open-source developer has created a logic bomb that will act as a wiper, which is a type of malware that destroys data on a system. This is an example of weaponization, as the developer has prepared a cyberweapon to sabotage the code repository.

The correct answer is A. Orange team.

An orange team is a team that is involved in facilitation and training of other teams in cybersecurity. An orange team assists the yellow team, which is the management or leadership team that oversees the cybersecurity strategy and governance of an organization. An orange team helps the yellow team to understand the cybersecurity risks and challenges, as well as the roles and responsibilities of other teams, such as the red, blue, and purple teams12.

In this scenario, the analyst is conducting monitoring against an authorized team that will perform adversarial techniques. This means that the analyst is observing and evaluating the performance of another team that is simulating real-world attacks against the organization’s systems or networks. This could be either a red team or a purple team, depending on whether they are working independently or collaboratively with the defensive team345.

The analyst interacts with the team twice per day to set the stage for the techniques to be used. This means that the analyst is providing guidance and feedback to the team on how to conduct their testing and what techniques to use. This could also involve setting up scenarios, objectives, rules of engagement, and success criteria for the testing. This implies that the analyst is facilitating and training the team to improve their skills and capabilities in cybersecurity12.

Therefore, based on these descriptions, the analyst is a member of an orange team, which is involved in facilitation and training of other teams in cybersecurity.

The other options are incorrect because they do not match the role and function of the analyst in this scenario.

Option B is incorrect because a blue team is a defensive security team that monitors and protects the organization’s systems and networks from real or simulated attacks. A blue team does not conduct monitoring against an authorized team that will perform adversarial techniques, but rather defends against them345.

Option C is incorrect because a red team is an offensive security team that discovers and exploits vulnerabilities in the organization’s systems or networks by simulating real-world attacks. A red team does not conduct monitoring against an authorized team that will perform adversarial techniques, but rather performs them345.

Option D is incorrect because a purple team is not a separate security team, but rather a collaborative approach between the red and blue teams to improve the organization’s overall security. A purple team does not conduct monitoring against an authorized team that will perform adversarial techniques, but rather works with them345.

Thepost-incident review processhelps an organization identify gaps in its response and security posture. Assigning different departmental groups ensures that flaws inspecific work areas (such as IT, HR, or legal teams)are identified and addressed​.

Option Bis incorrect because not all staff need exposure; the review focuses on relevant stakeholders.

Option Cis a part of the process, but the main goal is improvement, not just playbook verification.

Option D(cross-training) is a benefit but not the main objective.

Thus,A is the best answerbecause it focuses on identifyingflaws in specific areas of incident management.

Implementing segmentation with ACLs is the best solution to secure the network. Segmentation is the process of dividing a network into smaller subnetworks, or segments, based on criteria such as function, location, or security level. Segmentation can help improve the network performance, scalability, and manageability, as well as enhance the network security by isolating the sensitive or critical data and systems from the rest of the network. ACLs are Access Control Lists, which are rules or policies that specify which users, devices, or applications can access a network segment or resource, and which actions they can perform. ACLs can help enforce the principle of least privilege, and prevent unauthorized or malicious access to the network segments or resources12. Configuring logging and monitoring to the SIEM, deploying MFA to cloud storage locations, and rolling out an IDS are all good security practices, but they are not the best solution to secure the network. Logging and monitoring tothe SIEM can help detect and analyze the network events and incidents, but they do not prevent them. MFA can help authenticate the users who access the cloud storage locations, but it does not protect the network from attacks or breaches. IDS can help identify and alert the network intrusions, but it does not block them34 . References: Network Segmentation: What It Is and How to Do It Right, What is an Access Control List (ACL)? | IBM, What is SIEM? | Microsoft Security, What is Multifactor Authentication (MFA)? | Duo Security, [What is an Intrusion Detection System (IDS)? | IBM]

A nation-state actor is a group or individual that conducts cyberattacks on behalf of a government or a political entity. They are usually motivated by national interests, such as espionage, sabotage, or influence operations. They are often highly skilled, resourced, and persistent, and they operate with the protection or support of their state sponsors. Therefore, they are less likely to be concerned with the forensic analysis for legal action of their actions, as they are unlikely to face prosecution or extradition in their own country or by international law. They are more likely to be concerned with the detection by the MITRE ATT&CK framework, which is a knowledge base of adversary tactics and techniques based on real-world observations. The MITRE ATT&CK framework can help defenders identify, prevent, and respond to cyberattacks by nation-state actors. They are also likely to be concerned with the detection or prevention of reconnaissance activities, which are the preliminary steps of cyberattacks that involve gathering information about the target, such as vulnerabilities, network topology, or user credentials. Reconnaissance activities can expose the presence, intent, and capabilities of the attackers, and allow defenders to take countermeasures. Finally, they are likely to be concerned with the examination of their actions and objectives, which can reveal their motives, strategies, and goals, and help defenders understand their threat profile and attribution.

Comprehensive and Detailed Step-by-Step Explanation:Network segmentation supports zero-trust principles by ensuring sensitive systems are isolated and access is restricted based on identity, role, and context. Unlike traditional models, zero-trust architecture does not automatically trust authenticated users or internal network traffic. It enforces strict access controls to minimize risk.

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.

After detecting a compromised email server and unusual network traffic, the next step in incident response is containment, to prevent further damage or spread of the compromise. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 5: Incident Response, page 197.

Placing a legal hold on the employee’s mailbox is the best action to perform first, as it preserves all mailbox content, including deleted items and original versions of modified items, for potential legal or forensic purposes. A legal hold is a feature that allows an administrator to retain mailbox data for a user indefinitely or for a specified period, regardless of the user’s actions or retention policies. A legal hold can be applied to a mailbox using Litigation Hold or In-Place Hold in Exchange Server or Exchange Online. A legal hold can help to ensure that evidence of data exfiltration or other malicious activities is not lost or tampered with, and that the organization can comply with any legal or regulatory obligations. The other actions are not as urgent or effective as placing a legal hold on the employee’s mailbox, as they do not address the immediate threat of data loss or compromise. Enabling filtering on the web proxy may help to prevent some types of data exfiltration or malicious traffic, but it does nothelp to recover or preserve the data that has already been emailed externally. Disabling the public email access with CASB (Cloud Access Security Broker) may help to block or monitor the use of public email services by employees, but it does not help to recover or preserve the data that has already been emailed externally. Configuring a deny rule on the firewall may help to block or monitor the network traffic from the employee’s laptop, but it does not help to recover or preserve the data that has already been emailed externally.

Agent-based scansare runlocally on hostsvia installed agents, whichsignificantly reduces network trafficwhile allowing in-depth visibility and accurate scanning. They’re ideal for bandwidth-limited or sensitive networks.

Credentialed scans (A)still transmit data over the network.

Individual scans (B)is ambiguous and not a standard term.

Baseline scans (C)focus on policy compliance, not reducing traffic.

?Reference:

Chapple & Seidl – Vulnerability Management, Chapter 6: Scanning Techniques

CS0-003 Domain 2.1 – Vulnerability Scanning Methods