CompTIA CS0-003 Exam Practice Test Instant Access

Question 1

An attacker recently gained unauthorized access to a financial institution's database, which contains confidential information. The attacker exfiltrated a large amount of data before being detected and blocked. A security analyst needs to complete a root cause analysis to determine how the attacker was able to gain access. Which of the following should the analyst perform first?

ADocument the incident and any findings related to the attack for future reference.

BInterview employees responsible for managing the affected systems.

CReview the log files that record all events related to client applications and user access.

DIdentify the immediate actions that need to be taken to contain the incident and minimize damage.

Answer : C

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.

Question 2

An organization conducted a web application vulnerability assessment against the corporate website, and the following output was observed:

Which of the following tuning recommendations should the security analyst share?

ASet an Http Only flag to force communication by HTTPS.

BBlock requests without an X-Frame-Options header.

CConfigure an Access-Control-Allow-Origin header to authorized domains.

DDisable the cross-origin resource sharing header.

Answer : C

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.

Question 3

An analyst is designing a message system for a bank. The analyst wants to include a feature that allows the recipient of a message to prove to a third party that the message came from the sender Which of the following information security goals is the analyst most likely trying to achieve?

ANon-repudiation

BAuthentication

CAuthorization

DIntegrity

Answer : A

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.

Question 4

An organization has established a formal change management process after experiencing several critical system failures over the past year. Which of the following are key factors that the change management process will include in order to reduce the impact of system failures? (Select two).

AEnsure users the document system recovery plan prior to deployment.

BPerform a full system-level backup following the change.

CLeverage an audit tool to identify changes that are being made.

DIdentify assets with dependence that could be impacted by the change.

ERequire diagrams to be completed for all critical systems.

FEnsure that all assets are properly listed in the inventory management system.

Answer : D, F

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

D . Identify assets with dependence that could be impacted by the change.

F . Ensure that all assets are properly listed in the inventory management system.

D . Identify assets with dependence that could be impacted by the change: This is crucial in change management because understanding the interdependencies among assets can help anticipate and mitigate the potential cascading effects of a change. By identifying these dependencies, the organization can plan more effectively for changes and minimize the risk of unintended consequences that could lead to system failures.

F . Ensure that all assets are properly listed in the inventory management system: Maintaining an accurate and comprehensive inventory of assets is fundamental in change management. Knowing exactly what assets the organization possesses and their characteristics allows for better planning and impact analysis when changes are made. This ensures that no critical component is overlooked during the change process, reducing the risk of failures due to incomplete information.

Other Options:

A . Ensure users document system recovery plan prior to deployment: While documenting a system recovery plan is important, it's more related to disaster recovery and business continuity planning than directly reducing the impact of system failures due to changes.

B . Perform a full system-level backup following the change: While backups are essential, they are generally a reactive measure to recover from a failure, rather than a proactive measure to reduce the impact of system failures in the first place.

C . Leverage an audit tool to identify changes that are being made: While using an audit tool is helpful for tracking changes and ensuring compliance, it is not directly linked to reducing the impact of system failures due to changes.

E . Require diagrams to be completed for all critical systems: While having diagrams of critical systems is useful for understanding and managing them, it is not a direct method for reducing the impact of system failures due to changes. Diagrams are more about documentation and understanding rather than proactive change management.

Question 5

During an incident, analysts need to rapidly investigate by the investigation and leadership teams. Which of the following best describes how PII should be safeguarded during an incident?

AImplement data encryption and close the data so only the company has access.

BEnsure permissions are limited in the investigation team and encrypt the data.

CImplement data encryption and create a standardized procedure for deleting data that is no longer needed.

DEnsure that permissions are open only to the company.

Answer : B

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.

CompTIA CySA+ Study Guide: Exam CS0-002, 2nd Edition : CompTIA CySA+ Certification Exam Objectives Version 4.0.pdf)

Question 6

A SOC analyst is analyzing traffic on a network and notices an unauthorized scan. Which of the following types of activities is being observed?

APotential precursor to an attack

BUnauthorized peer-to-peer communication

CRogue device on the network

DSystem updates

Answer : A

Question 7

The SOC receives a number of complaints regarding a recent uptick in desktop error messages that are associated with workstation access to an internal web application. An analyst, identifying a recently modified XML file on the web server, retrieves a copy of this file for review, which contains the following code:

Which of The following XML schema constraints would stop these desktop error messages from appearing?

AOption A

BOption B

COption C

DOption D

Answer : B

The XML file contains JavaScript embedded within a <description> tag that executes an alert message, which is a common Cross-Site Scripting (XSS) attack vector. The issue occurs because the XML schema does not restrict the input to safe characters, allowing arbitrary script execution when the XML file is processed by a vulnerable application.

Solution: Implement Input Validation Using an XML Schema Constraint

Option B enforces a whitelist approach by allowing only alphanumeric characters and spaces ([a-zA-Z 0-9]*).

This prevents the inclusion of malicious JavaScript or special characters such as <, >, or &, which are required for XSS injection.

Why are the other options incorrect?

Option A: Restricts input to a Social Security Number (SSN) format ([0-9]{3}-[0-9]{2}-[0-9]{4}). While it prevents JavaScript injection, it is too restrictive and would break legitimate text-based content in the XML.

Option C: Restricts input to only numeric values ([0-9]*), preventing JavaScript injection but also breaking legitimate non-numeric content in the <description> field.

Option D: Restricts input to a single positive integer, which does not align with the expected text-based content.

Thus, Option B is the correct answer, as it enforces proper input validation while still allowing expected text input.

CompTIA Cybersecurity Analyst (CySA+) CS0-003 Exam Practice Test