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

This command uses a Wireshark display filter (-Y) to show packets that match either HTTP or UDP:

http matches HTTP protocol traffic, which is unencrypted web traffic (i.e., not HTTPS/TLS). To view encrypted web requests (HTTPS), you would need SSL/TLS decryption support and a proper setup (keys, etc.). The All-in-One guide explicitly notes Wireshark/TShark support for SSL/TLS decryption to view encrypted traffic, implying encrypted web traffic isn’t simply “http” unless decrypted and dissected accordingly.

udp matches all UDP traffic, and DNS commonly uses UDP/53, so DNS packets will be included as part of UDP traffic.

Supporting extracts from the All-in-One guide about filtering and web ports (HTTP/HTTPS) and TLS decryption capabilities:

Exact extract (All-in-One Exam Guide):

“Port filters… Example: tcp port 80 or tcp port 443”

Exact extract (All-in-One Exam Guide):

“Support for SSL/TLS decryption to view encrypted traffic”

Therefore: The filter shows unencrypted web (HTTP) traffic and UDP traffic (which includes DNS), making B the best match.

A tabletop exercise is a type of simulation exercise that involves testing possible incident scenarios and how to react properly, without actually performing any actions or using any resources. A tabletop exercise is usually conducted by a facilitator who presents a realistic scenario to a group of participants, such as a cyberattack, a natural disaster, or a data breach. The participants then discuss and evaluatetheir roles, responsibilities, plans, procedures, and policies for responding to the incident, as well as the potential impacts and outcomes. A tabletop exercise can help identify strengths and weaknesses in the incident response plan, improve communication and coordination among the stakeholders, raise awareness and preparedness for potential incidents, and provide feedback and recommendations for improvement.

The most likely reason for this vulnerability is B. The developer did not set proper cross-site scripting protections in the header. Cross-site scripting (XSS) is a type of web application vulnerability that allows an attacker to inject malicious code into a web page that is viewed by other users. XSS can be used to steal cookies, session tokens, credentials, or other sensitive information, or to perform actions on behalf of the victim1.

One of the common ways to prevent XSS attacks is to set proper HTTP response headers that instruct the browser how to handle the content of the web page. For example, the Content-Type header can specify the MIME type and character encoding of the web page, which can help the browser avoid interpreting data as code. The X-XSS-Protection header can enable or disable the browser’s built-in XSS filter, which can block or sanitize suspicious scripts. The Content-Security-Policy header can define a whitelist of sources and directives that control what resources and scripts can be loaded or executed on the web page2.

According to the output of Arachni, a web application security scanner framework3, it detected an XSS vulnerability in the form input ‘txtSearch’ with action https://localhost/search.aspx. This means that Arachni was able to inject a malicious script into the input field and observe its execution in the response. This indicates that the developer did not set proper cross-site scripting protections in the header of search.aspx, which allowed Arachni to bypass the browser’s default security mechanisms and execute arbitrary code on the web page.

One of the best actions to take after the conclusion of a security incident to improve incident response in the future is to schedule a review with all teams to discuss what occurred, what went well, what went wrong, and what can be improved. This review is also known as a lessons learned session or an after-action report. The purpose of this review is to identify the root causes of the incident, evaluate the effectiveness of the incident response process, document any gaps or weaknesses in the security controls, and recommend corrective actions or preventive measures for future incidents. Official References: https://www.eccouncil.org/cybersecurity-exchange/threat-intelligence/cyber-kill-chain-seven-steps-cyberattack/

Increasing training and awareness for all staff is the best way to address the issue of employees being enticed to assist attackers by visiting specific websites and running downloaded files when prompted by phone calls. This issue is an example of social engineering, which is a technique that exploits human psychology and behavior to manipulate people into performing actions or divulging information that benefit the attackers. Social engineering can take many forms, such as phishing, vishing, baiting, quid pro quo, or impersonation. The best defense against social engineering is to educate and train the staff on how to recognize and avoid common social engineering tactics, such as:

Verifying the identity and legitimacy of the caller or sender before following their instructions or clicking on any links or attachments

Being wary of unsolicited or unexpected requests for information or action, especially if they involve urgency, pressure, or threats

Reporting any suspicious or anomalous activity to the security team or the appropriate authority

Following the organization’s policies and procedures on security awareness and best practices

Official References:

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

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

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

The best practice that the company should follow with this proxy is to decommission the proxy. Decommissioning the proxy involves removing or disposing of the proxy from the rack and the network, as well as deleting or wiping any data or configuration on the proxy. Decommissioning the proxy can help eliminate the vulnerability on the proxy, as well as reduce the attack surface, complexity, or cost of maintaining the network. Decommissioning the proxy can also free up space or resources for other devices or systems that are in use or needed by the company.

The first action that the analyst should take in this case is to clone the virtual server for forensic analysis. Cloning the virtual server involves creating an exact copy or image of the server’s data and state at a specific point in time. Cloning the virtual server can help preserve and protect any evidence or information related to the security incident, as well as prevent any tampering, contamination, or destruction of evidence. Cloning the virtual server can also allow the analyst to safely analyze and investigate the incident without affecting the original server or its operations.

Log entry 4 shows an attempt to exploit the zero-day command injection vulnerability by appending a malicious command (;cat /etc/passwd) to the end of a legitimate request (/cgi-bin/index.cgi?name=John). This command would try to read the contents of the /etc/passwd file, which contains user account information, and could lead to further compromise of the system. The other log entries do not show any signs of command injection, as they do not contain any special characters or commands that could alter the intended behavior of the application. Official References:

https://www.imperva.com/learn/application-security/command-injection/

https://www.zerodayinitiative.com/advisories/published/

SIEM (Security Information and Event Management) technology aggregates and analyzes activity from many different resources across your IT infrastructure. The description of correlating information from various sources and triggering notifications aligns with the capabilities of a SIEM system.

The correct answer is D. MITRE ATT & CK.

MITRE ATT & CK is a framework that maps the tactics, techniques, and procedures (TTPs) of various threat actors and groups, based on real-world observations and data. MITRE ATT & CK can help a Chief Information Security Officer (CISO) to map all the attack vectors that the company faces each day, as well as to align their security controls around the most relevant and prevalent threats. MITRE ATT & CK can also help the CISO to assess the effectiveness and maturity of their security posture, as well as to identify and prioritize the gaps and improvements .

The other options are not the best recommendations for mapping all the attack vectors that the company faces each day. OSSTMM (Open Source Security Testing Methodology Manual) (A) is a methodology that provides guidelines and best practices for conducting security testing and auditing, but it does not map the TTPs of threat actors or groups. Diamond Model of Intrusion Analysis (B) is a model that analyzes the relationships and interactions between four elements of an intrusion: adversary, capability, infrastructure, and victim. The Diamond Model can help understand the characteristics and context of an intrusion, but it does not map the TTPs of threat actors or groups. OWASP (Open Web Application Security Project) © is a project that provides resources and tools for improving the security of web applications, but it does not map the TTPs of threat actors or groups.

This scenario describes a strictgovernance policyrequiring multiple approvals for high-risk security group changes.Organizational governancerefers to policies that enforce security controls and approval workflows​.

Option B (MOU - Memorandum of Understanding)refers to agreements between parties, not internal security processes.

Option C (SLA - Service Level Agreement)refers to service guarantees, not security governance.

Option D (Business process interruption)might be a consequence, but it is not the primaryinhibitor to remediationin this case.

Thus,A is correct, as governance rules are restricting remediation speed.

The correct answer is A. To provide metrics and test continuity controls.

A disaster recovery exercise is a simulation or a test of the disaster recovery plan, which is a set of procedures and resources that are used to restore the normal operations of an organization after a disaster or a major incident. The goal of a disaster recovery exercise is to provide metrics and test continuity controls, which are the measures that ensure the availability and resilience of the critical systems and processes of an organization. A disaster recovery exercise can help evaluate the effectiveness, efficiency, and readiness of the disaster recovery plan, as well as identify and address any gaps or issues .

The other options are not the best descriptions of the goal of a disaster recovery exercise. Verifying the roles of the incident response team (B) is a goal of an incident response exercise, which is a simulation or a test of the incident response plan, which is a set of procedures and roles that are used to detect, contain, analyze, and remediate an incident. Providing recommendations for handling vulnerabilities © is a goal of a vulnerability assessment, which is a process of identifying and prioritizing the weaknesses and risks in an organization’s systems or network. Performing tests against implemented security controls (D) is a goal of a penetration test, which is an authorized and simulated attack on an organization’s systems or network to evaluate their security posture and identify any vulnerabilities or misconfigurations.

A “network data closet” attack is a physical-environment incident (hardware, cabling, physical access/tampering). Proper documentation in such cases includes documenting the scene and physical state of impacted items so that investigators can reconstruct what was present, what was changed, and how things were connected.

The All-in-One CySA+ guide explicitly states that an important step is documenting the physical environment and that an easy way is to take lots of photos of the scene:

Exact extract (All-in-One Exam Guide):

“Another important… step is to document the entire physical environment around a device. An easy way to do this is to take lots of photos of the scene.”

Why the other options are less correct:

A is a recovery/ops task, not primary incident documentation of a physical attack scene.

B may be useful in some contexts, but the best practice for a physical incident scene is to photograph impacted items and surroundings.

C can help later, but it’s not the first/best documentation action for a physical tampering incident compared to capturing the scene as-found.

nessie.explosion should be prioritized for remediation, as it has the highest CVSSv3.1 exploitability score of 8.6. The exploitability score is a sub-score of the CVSSv3.1 base score, which reflects the ease and technical means by which the vulnerability can be exploited. The exploitability score is calculated based on four metrics: Attack Vector, Attack Complexity, Privileges Required, and User Interaction. The higher the exploitability score, the more likely and feasible the vulnerability is to be exploited by an attacker12. nessie.explosion has the highest exploitability score because it has the lowest values for all four metrics: Network (AV:N), Low (AC:L), None (PR:N), and None (UI:N). This means that the vulnerability can be exploited remotely over the network, without requiring any user interaction or privileges, and with low complexity. Therefore, nessie.explosion poses the greatest threat to the end user workstations, and should be remediated first. vote.4p, sweet.bike, and great.skills have lower exploitability scores because they have higher values for some of the metrics, such as Adjacent Network (AV:A), High (AC:H), Low (PR:L), or Required (UI:R). This means that the vulnerabilities are more difficult or less likely to be exploited, as they require physical proximity, user involvement, or some privileges34. References: CVSS v3.1 Specification Document - FIRST, NVD - CVSS v3 Calculator, CVSS v3.1 User Guide - FIRST, CVSS v3.1 Examples - FIRST

SLA stands for service level agreement, which is a contract or document that defines the expectations and obligations between a service provider and a customer regarding the quality, availability, performance, or scope of a service. An SLA may also specify the metrics, penalties, or remedies for measuring or ensuring compliance with the agreed service levels. An SLA can help the SOC manager review if the team is meeting the appropriate contractual obligations for the customer, such as response time, resolution time, reporting frequency, or communication channels.

Documenting the process in a step-by-step format on the team wiki ensures the junior analyst has a clear, repeatable reference. This approach also supports consistency and accuracy, and the documentation can be updated or referenced by other team members as needed. CompTIA emphasizes the importance of procedural documentation in both CySA+ and Security+ for ensuring team members have reliable resources for task execution, which aids in knowledge retention and standardized practices across the team.

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 because CVSS severity alone is not enough to confirm remediation priority. The vulnerability manager needs to know the criticality of the affected hosts/assets. For example, a slightly lower CVSS vulnerability on a public-facing, business-critical system may require faster remediation than a higher CVSS vulnerability on a low-value internal system.

The CySA+ All-in-One guide states that remediation priority should consider exploitability, whether a vulnerability is weaponized, patch availability, and asset value and criticality. It also explains that analysts must consider business impact when deciding how to remediate vulnerabilities.

The Secbay CySA+ guide also explains that vulnerability prioritization should evaluate severity, exploitability, and the criticality of affected systems, including business operations, data sensitivity, and regulatory impact.

Why the other options are incorrect:

B is incorrect because SLA information determines remediation timelines after priority is established.

C is incorrect because KPIs measure performance, not asset priority.

D is incorrect because the scenario does not state these are zero-day vulnerabilities.

The behavior described is a high-level objective: gain unauthorized access to a vulnerable system. In MITRE ATT & CK, tactics represent the attacker’s high-level goals (the “why”), such as gaining initial access. That makes this observation a tactic-level description rather than a technique/procedure.

The All-in-One CS0-003 guide defines tactics as high-level goals and explicitly includes “gaining initial access” as an example:Exact extract (All-in-One Exam Guide): “Tactics The high-level goals attackers are trying to achieve, such as gaining initial access, persistence, or exfiltrating data.”

It also describes Initial access as the goal of gaining a foothold (i.e., unauthorized access) into a target system/network:Exact extract (All-in-One Exam Guide): “Initial access. Tactics used by attackers to gain a foothold within a target network or system…”

Why the other options are not correct:

B (Techniques): Techniques are the specific methods used to accomplish a tactic (the “how”), not the high-level goal itself.Exact extract (All-in-One Exam Guide): “Techniques The specific methods and procedures attackers use to achieve their goals.”

A (Procedures): Procedures are the step-by-step sequences for executing techniques (an attacker’s “attack playbook”), not the high-level goal statement.

D (Subtechniques): Subtechniques are more granular breakdowns under a technique; your statement doesn’t describe a specific technique, so it can’t be placed at the subtechnique level.

References (CompTIA CySA+ CS0-003 documents / study guides used):

Mya Heath et al., CompTIA CySA+ All-in-One Exam Guide (CS0-003): tactics are high-level goals (e.g., gaining initial access); initial access definition; techniques definition; procedures as step-by-step sequences