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

The correct answer is D. Registry.

The registry is a database that stores system configuration keys and values in a Windows environment. The registry contains information about the hardware, software, users, and preferences of the system. The registry can be accessed and modified using the Registry Editor tool (regedit.exe) or the command-line tool (reg.exe). The registry is organized into five main sections, called hives, which are further divided into subkeys and values.

The other options are not the best descriptions of where the analyst can find system configuration keys and values in a Windows environment. config.ini (A) is a file that stores configuration settings forsome applications, but it is not a database that stores system configuration keys and values. ntds.dit (B) is a file that stores the Active Directory data for a domain controller, but it is not a database that stores system configuration keys and values. Master boot record © is a section of the hard disk that contains information about the partitions and the boot loader, but it is not a database that stores system configuration keys and values.

A discovery scan is a type of web application scanning that involves identifying active, internet-facing web applications and their URIs, without performing any intrusive or in-depth tests. This type of scan can help to understand the scope and structure of a web application before conducting more comprehensive vulnerability scans12. References: 1: OWASP Vulnerability Scanning Tools 2: CISA Web Application Scanning

The function that can be used on a shell script to identify anomalies on the network routing most accurately is:

function x() { info=(dig(dig -x $1 | grep PTR | tail -n 1 | awk -F “.in-addr” ’{print $1} ' ).origin.asn.cymru.com TXT +short) & & echo “$1 | $info” }

This function takes an IP address as an argument and performs two DNS lookups using the dig command. The first lookup uses the -x option to perform a reverse DNS lookup and get the hostname associated with the IP address. The second lookup uses the origin.asn.cymru.com domain to get the autonomous system number (ASN) and other information related to the IP address. The function then prints the IP address and the ASN information, which can help identify any routing anomalies or inconsistencies

An incident response timeline is a detailed chronological record of all events and actions taken during the response to a security incident. It includes timestamps and descriptions of each step, providing a comprehensive overview of how the incident was detected, contained, mitigated, and resolved. This timeline is crucial for post-incident analysis, helping to understand the effectiveness of the response, identify areas for improvement, and ensure accountability and transparency in the incident handling process.

The formal incident declaration is crucial to identify and document the staff who have the authority to declare an incident, ensuring that incidents are handled by authorized personnel. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 5: Incident Response, page 197.

In this scenario, the security analyst is presented with multiple vulnerabilities, including a critical zero-day vulnerability affecting the web server with a CVSS score of 10. The CVSS (Common Vulnerability Scoring System) provides a standardized method for rating IT vulnerabilities, with a score of 10 indicating the highest severity.

Option A:Contact the web systems administrator and request that they shut down the asset.

Correct Choice:Given the critical nature of a zero-day vulnerability with a CVSS score of 10, immediate action is warranted to prevent potential exploitation. Shutting down the affected web server reduces the attack surface and mitigates the risk until a patch or workaround is available. This aligns with incident response best practices, where containment is a priority to prevent further damage.

Option B:Monitor the patch releases for all items and escalate patching to the appropriate team.

Incorrect Choice:While monitoring for patches is essential, it is a reactive approach. In the case of a zero-day vulnerability with active exploitation potential, waiting for a patch without implementing immediate protective measures exposes the organization to significant risk.

Option C:Run the vulnerability scan again to verify the presence of the critical finding and the zero-day vulnerability in the environment.

Incorrect Choice:Re-scanning may confirm the vulnerability ' s presence but does not address the immediate threat. Action to mitigate the risk should take precedence over verification, especially when the vulnerability is known and critical.

Option D:Forward the advisory to the web security team and initiate the prioritization strategy for the other vulnerabilities.

Incorrect Choice:Communicating with the web security team is important; however, in the face of a critical zero-day vulnerability, immediate action (such as shutting down the affected asset) is necessary before addressing other vulnerabilities.

A social engineering attack is underway is the most likely explanation for the outbound traffic to a host IP that resolves to https://offce365password.acme.co, while the site’s standard VPN logon page is www.acme.com/logon. A social engineering attack is a technique that exploits human psychology and behavior to manipulate people into performing actions or divulging information that benefit the attackers. A common type of social engineering attack is phishing, which involves sending fraudulent emails or other messages that appear to come from a legitimate source, such as a company or a colleague, and lure the recipients into clicking on malicious links or attachments, or entering their credentials or other sensitive information on fake websites. In this case, the attackers may have registered a domain name that looks similar to the company’s domain name, but with a typo (offce365 instead of office365), and set up a fake website that mimics the company’s VPN logon page. The attackers may have also sent phishing emails to the company’s employees, asking them to reset their passwords or log in to their VPN accounts using the malicious link. The security analyst should investigate the source and content of the phishing emails, and alert the employees not to click on any suspicious links or enter their credentials on any untrusted websites. 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 correct answer is B. CASB. A Cloud Access Security Broker is specifically designed to sit between users and cloud services, monitor cloud activity, enforce access policies, and provide visibility into unauthorized cloud storage use. This directly matches the question’s requirement: showing user access to prohibited cloud storage and whether a file was downloaded to a personal device.

Exact supporting extract: the All-in-One CySA+ guide explains that a CASB “sits between each user and each cloud service,” monitors activity, enforces policies, and alerts when something is wrong. It also lists visibility as a CASB pillar, including whether users are connecting to unauthorized resources such as cloud storage not controlled by the organization.

The Sybex CySA+ Study Guide also states that CASB tools enforce security policies when cloud resources and services are used, and can help with data security, service usage and access visibility, and risk management.

The official CompTIA CySA+ CS0-003 objectives include Cloud Access Security Broker (CASB) under identity and access management / security operations architecture concepts.

Why the other options are incorrect:

A. SASE is broader architecture that may include CASB, SWG, FWaaS, and SD-WAN, but the specific tool for cloud-service visibility and policy logging is CASB.

C. EDR focuses on endpoint detection and response, not cloud storage access monitoring across cloud services.

D. SDN is software-defined networking and does not provide user-level cloud storage access logs.

A Secure Software Development Life Cycle (SDLC) integrates security measures at each stage of development to reduce vulnerabilities and improve the overall security of the software. This is essential for minimizing risks related to software usage and ensuring compliance with regulatory requirements, which is particularly important for organizations handling sensitive data. As per CompTIA standards, a Secure SDLC helps prevent security breaches and protects both the organization and its users from potential harm. Options A, C, and D do not accurately describe the primary goals of a Secure SDLC, which primarily centers on risk reduction and regulatory compliance.

Timeline analysis in digital forensics involves creating a chronological sequence of events based on system logs, file changes, and other forensic data. This process often uses graphical representations to illustrate and analyze how an incident unfolded over time, making it easier to identify key events and potential indicators of compromise. This approach is highlighted in CompTIA Cybersecurity Analyst (CySA+) practices as crucial for understanding the scope and sequence of a security incident. The other options do not involve chronological or graphical analysis to the extent that timeline analysis does.

To determine the correct vulnerability, you must map the specific threat intelligence (users clicking email links) to the CVSS Base Metrics provided in the table.

1. Analyze the Scenario:

Threat Vector: " End users frequently click on malicious links sent via email. "

Attack Vector implication: The attack is coming from outside the organization (remote), meaning the Attack Vector must be Network.

Interaction implication: The success of the attack relies on the user performing an action (clicking), meaning User Interaction must be Yes (Required).

2. Evaluate the Table:

Vulnerability

Attack Vector

Attack Complexity

Auth Required

User Interaction

Analysis

A

Network

Low

No

Yes

Perfect Match. This represents a remote exploit (e.g., a browser drive-by download or malicious site) that triggers when a user clicks a link. It requires no authentication and is easy to execute.

B

Local

Low

Yes

Yes

Incorrect. " Local " usually implies the attacker already has physical access or a foothold. " Auth Required " makes it harder to exploit than A.

C

Network

High

Yes

Yes

Incorrect. " High " complexity and " Auth Required " make this significantly less likely/severe than A for a mass phishing campaign.

D

Local

Low

No

No

Incorrect. " Local " vector and " User Interaction: No " do not align with the specific threat of users clicking links.

3. Conclusion:

Vulnerability A is the highest risk because it is Remotely Exploitable (Network), easy to perform (Complexity: Low), requires No Authentication (anyone who clicks is vulnerable), and directly targets the behavior identified in the threat intelligence (User Interaction: Yes).

Attack Vector (AV:N): The context of " email " typically maps to Network because the payload is delivered over the internet/network stack.

User Interaction (UI:R): CompTIA defines this metric as required when a user must perform an action (like clicking a link or opening an attachment) for the vulnerability to be successfully exploited.

Risk Prioritization: Vulnerabilities with Network vectors and Low complexity are generally prioritized over Local/High Complexity ones because they are easier to scale and automate.

XSS is a type of web application attack that exploits the vulnerability of a web server or browser to execute malicious scripts or commands on the client-side. XSS attackers inject malicious code, such as JavaScript, VBScript, HTML, or CSS, into a web page or application that is viewed by other users. The malicious code can then access or manipulate the user’s session, cookies, browser history, or personal information, or perform actions on behalf of the user, such as stealing credentials, redirecting to phishing sites, or installing malware12

The line in the web server log shows an example of an XSS attack using VBScript. The attacker tried to insert an < IMG > tag with a malicious SRC attribute that contains a VBScript code. The VBScript code is intended to display a message box with the text “test” when the user views the web page or application. This is a simple and harmless example of XSS, but it could be used to test the vulnerability of the web server or browser, or to launch more sophisticated and harmful attacks3

The security analyst is validating a Local File Inclusion (LFI) vulnerability, as indicated by the “/…/…/…/” in the GET request which is a common indicator of directory traversal attempts associated with LFI. The other options are not relevant for this purpose: SQL injection involves injecting malicious SQL statements into a database query; XSS involves injecting malicious scripts into a web page; CSRF involves tricking a user into performing an unwanted action on a web application.

1. How many employees clicked on the link in the phishing email?

According to the email server logs, 25 employees clicked on the link in the phishing email.

2. On how many workstations was the malware installed?

According to the file server logs, the malware was installed on 15 workstations.

3. What is the executable file name of the malware?

The executable file name of the malware is svchost.EXE.

Answers

1. 25

2. 15

3. svchost.EXE

The best option to quickly find out whether the IP address in a SIEM alert is a known-malicious IP address is C. Add data enrichment for IPS in the ingestion pipeline.

Data enrichment is the process of adding more information and context to raw data, such as IP addresses, by using external sources. Data enrichment can help analysts to gain more insights into the nature and origin of the threats they face, and to prioritize and respond to them accordingly. Dataenrichment for IPS (Intrusion Prevention System) means that the IPS can use enriched data to block or alert on malicious traffic based on various criteria, such as geolocation, reputation, threat intelligence, or behavior. By adding data enrichment for IPS in the ingestion pipeline, analysts can leverage the IPS’s capabilities to filter out known-malicious IP addresses before they reach the SIEM, or to tag them with relevant information for further analysis. This can save time and resources for the analysts, and improve the accuracy and efficiency of the SIEM.

The other options are not as effective or efficient as data enrichment for IPS in the ingestion pipeline. Joining an information sharing and analysis center (ISAC) specific to the company’s industry (A) can provide valuable threat intelligence and best practices, but it may not be timely or comprehensive enough to cover all possible malicious IP addresses. Uploading threat intelligence to the IPS in STIX/TAXII format (B) can help the IPS to identify and block malicious IP addresses based on standardized indicators of compromise, but it may require manual or periodic updates and integration with the SIEM. Reviewing threat feeds after viewing the SIEM alert (D) can help analysts to verify and contextualize the malicious IP addresses, but it may be too late or too slow to prevent or mitigate the damage. Therefore, C is the best option among the choices given.

Mean time to detect (MTTD) is the best metric for an organization to focus on given recent investments in SIEM, SOAR, and a ticketing system. MTTD is a metric that measures how long it takes to detect a security incident or threat from the time it occurs. MTTD can be improved by using tools and processes that can collect, correlate, analyze, and alert on security data from various sources. SIEM, SOAR, and ticketing systems are examples of such tools and processes that can help reduce MTTD and enhance security operations. Official References: https://www.eccouncil.org/cybersecurity-exchange/threat-intelligence/cyber-kill-chain-seven-steps-cyberattack

Passive network foot printing is the best description of the example, as it reflects the technique of collecting information about a network or system by monitoring or sniffing network traffic without sending any packets or interacting with the target. Foot printing is a term that refers to the process of gathering information about a target network or system, such as its IP addresses, open ports, operating systems, services, or vulnerabilities. Foot printing can be done for legitimate purposes, such as penetration testing or auditing, or for malicious purposes, such as reconnaissance or intelligence gathering. Foot printing can be classified into two types: active and passive. Active foot printing involves sending packets or requests to the target and analyzing the responses, such as using tools like ping, traceroute, or Nmap. Active foot printing can provide more accurate and detailed information, but it can also be detected by firewalls or intrusion detection systems (IDS). Passive foot printing involves observing or capturing network traffic without sending any packets or requests to the target, such as using tools like tcpdump, Wireshark, or Shodan. Passive foot printing can provide less information, but it can also avoid detection by firewalls or IDS. The example in the question shows that the attacker has gained access to the syslog server on a LAN and reviewed the syslog entries to prioritize possible next targets. A syslog server is a server that collects and stores log messages from various devices or applications on a network. A syslog entry is a record of an event or activity that occurred on a device or application, such as an error, a warning, or an alert. By reviewing the syslog entries, the attacker can obtain information about the network or system, such as its configuration, status, performance, or security issues. This is an example of passive network foot printing, as the attacker is not sending any packets or requests to the target, but rather observing or capturing network traffic from the syslog server. The other options are not correct, as they describe different techniques or concepts. OS fingerprinting is a technique of identifying the operating system of a target by analyzing its responses to certain packets or requests, such as using tools like Nmap or Xprobe2. OS fingerprinting can be done actively or passively, but it is not what the attacker is doing in the example. Service port identification is a technique of identifying the services running on a target by scanning its open ports and analyzing its responses to certain packets or requests, such as using tools like Nmap or Netcat. Service port identification can be done actively or passively, but it is not what the attacker is doing in the example. Application versioning is a concept that refers to the process of assigning unique identifiers to different versions of an application, such as using numbers, letters, dates, or names. Application versioning canhelp to track changes, updates, bugs, or features of an application, but it is not related to what the attacker is doing in the example.

Non-repudiation ensures that a message sender cannot deny the authenticity of their sent message. This is crucial in banking communications for legal and security reasons.

The goal of allowing a message recipient to prove the message ' s origin is non-repudiation. This ensures that the sender cannot deny the authenticity of their message. Non-repudiation is a fundamental aspect of secure messaging systems, especially in banking and financial communications.

The correct answer is D. Diamond Model of Intrusion Analysis. The Diamond Model is used to analyze intrusions by examining the relationships between the adversary, capability, infrastructure, and victim. This makes it useful for understanding how an adversary operates, including their tools, infrastructure, tactics, techniques, and procedures.

Exact supporting extract: the Secbay CySA+ guide explains that the Diamond Model highlights four components: adversary, capabilities, infrastructure, and victims. It further states that the adversary element focuses on understanding the adversary’s capabilities, intentions, motivations, tactics, techniques, procedures, and objectives.

The All-in-One CySA+ guide also explains that the Diamond Model provides a structured approach to analyzing cyberattacks and that its four components provide a comprehensive view of an intrusion, allowing analysts to identify attackers’ goals, motivations, tactics, techniques, and infrastructure.

Why the other options are incorrect:

A. OWASP is focused mainly on web application security testing, not adversary method analysis.

B. Penetration Test Framework is used to structure penetration testing activities, not to model adversary intrusion behavior.

C. OSSTMM is a security testing methodology for evaluating systems, networks, and applications.

D. Diamond Model of Intrusion Analysis is best because it is specifically designed to analyze adversary behavior and intrusion relationships.