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

Answer : C

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.

Answer : D

Comprehensive and Detailed Explanation From Exact Extract:

Because the system is mission critical and there is no patch and no vendor support, the best risk-reduction approach is to implement compensating controls. Compensating controls are specifically recommended when immediate remediation is not possible, and for legacy systems where patches may not exist.

The Sybex CySA+ Study Guide states this directly:

Exact extract (Sybex Study Guide): ''Legacy systems may not have patches available, meaning that compensating controls may be the only option available.''

Secbay Press also explains that legacy systems may lack vendor support/updates and that mitigation strategies like compensating controls or isolation are essential to reduce risk:

Exact extract (Secbay Press): ''Legacy systems may lack vendor support and updates, making mitigation strategies essential... Implement specific mitigation strategies for legacy systems, such as compensating controls or isolation.''

And Secbay provides a legacy-system compensating control case study showing exactly the kinds of controls mentioned in option D---segmentation/isolation, access controls, and enhanced monitoring/continuous monitoring:

Exact extract (Secbay Press): ''Selected compensating controls, such as network segmentation, intrusion detection systems, and enhanced monitoring, to mitigate the risks...''

Why the other options are not ''best'' given the constraints:

A (Decommission immediately): may be ideal long-term, but conflicts with ''mission critical'' (and ''immediately'' is often unrealistic for business operations).

B (Block inbound/allow outbound): helps somewhat but is incomplete and can still allow command-and-control or exfiltration outbound; also doesn't address restricted admin access/monitoring comprehensively.

C (WAF): useful only if this is specifically a web application exposure; the scenario says ''legacy system'' broadly. Compensating controls are the most complete and universally applicable choice.

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

Chapple/Seidl, CompTIA CySA+ Study Guide (CS0-003): legacy systems may have no patches; compensating controls may be the only option

Secbay Press, CompTIA CySA+ Exam Prep Guide (CS0-003): legacy systems lack support/updates; use compensating controls or isolation

Answer : C

Automation is the best concept to describe the example, as it reflects the use of technology to perform tasks or processes without human intervention. Automation can help to improve efficiency, accuracy, consistency, and scalability of various operations, such as identity and access management (IAM). IAM is a security framework that enables organizations to manage the identities and access rights of users and devices across different systems and applications. IAM can help to ensure that only authorized users and devices can access the appropriate resources at the appropriate time and for the appropriate purpose. IAM can involve various tasks or processes, such as authentication, authorization, provisioning, deprovisioning, auditing, or reporting. Automation can help to simplify and streamline these tasks or processes by using software tools or scripts that can execute predefined actions or workflows based on certain triggers or conditions. For example, automation can help to create, update, or delete user accounts in bulk based on a file or a database, rather than manually entering or modifying each account individually. The example in the question shows that an API is used to insert bulk access requests from a file into an identity management system. An API (Application Programming Interface) is a set of rules or specifications that defines how different software components or systems can communicate and exchange data with each other. An API can help to enable automation by providing a standardized and consistent way to access and manipulate data or functionality of a software component or system. The example in the question shows that an API is used to automate the process of inserting bulk access requests from a file into an identity management system, rather than manually entering each request one by one. The other options are not correct, as they describe different concepts or techniques. Command and control is a term that refers to the ability of an attacker to remotely control a compromised system or device, such as using malware or backdoors. Command and control is not related to what is described in the example. Data enrichment is a term that refers to the process of enhancing or augmenting existing data with additional information from external sources, such as adding demographic or behavioral attributes to customer profiles. Data enrichment is not related to what is described in the example. Single sign-on is a term that refers to an authentication method that allows users to access multiple systems or applications with one set of credentials, such as using a single username and password for different websites or services. Single sign-on is not related to what is described in the example.

Answer : D

The MITRE ATT&CK framework is a knowledge base of cybercriminals' adversarial behaviors based on cybercriminals' known tactics, techniques and procedures (TTPs). It helps security teams model, detect, prevent and fight cybersecurity threats by simulating cyberattacks, creating security policies, controls and incident response plans, and sharing information with other security professionals. It is an open-source project that evolves with input from a global community of cybersecurity professionals1. Reference: What is the MITRE ATT&CK Framework? | IBM

Answer : D

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 Reference:

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

Answer : A

The most likely scenario occurring with the time stamps is that the NTP server is not configured on the host. NTP is the Network Time Protocol, which is used to synchronize the clocks of computers over a network. NTP uses a hierarchical system of time sources, where each level is assigned a stratum number. The most accurate time sources, such as atomic clocks or GPS receivers, are at stratum 0, and the devices that synchronize with them are at stratum 1, and so on. NTP clients can query multiple NTP servers and use algorithms to select the best time source and adjust their clocks accordingly1. If the NTP server is not configured on the host, the host will rely on its own hardware clock, which may drift over time and become inaccurate. This can cause discrepancies in the time stamps between the host and other devices on the network, such as the firewall, which may be synchronized with a different NTP server or use a different time zone. This can affect the security analysis and correlation of events, as well as the compliance and auditing of the network23. Reference: How the Windows Time Service Works, Time Synchronization - All You Need To Know, Firewall rules logging: a closer look at our new network compliance and ...

Answer : D

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.

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