Most Recent CompTIA CS0-003 Exam Questions & Answers

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.

Hacktivists are threat actors who use cyberattacks to promote a social or political cause, such as environmentalism, human rights, or democracy. They may target companies that they perceive as violating their values or harming the public interest. Hacktivists often use techniques such as defacing websites, launching denial-of-service attacks, or leaking sensitive data to expose or embarrass their targets12. Reference: An introduction to the cyber threat environment, page 3; What is a Threat Actor? Types & Examples of Cyber Threat Actors, section 2.

Vulnerability B is the vulnerability that the analyst should be most concerned about, knowing that end users frequently click on malicious links sent via email. Vulnerability B is a remote code execution vulnerability in Microsoft Outlook that allows an attacker to run arbitrary code on the target system by sending a specially crafted email message. This vulnerability is very dangerous, as it does not require any user interaction or attachment opening to trigger the exploit. The attacker only needs to send an email to the victim's Outlook account, and the code will execute automatically when Outlook connects to the Exchange server. This vulnerability has a high severity rating of 9.8 out of 10, and it affects all supported versions of Outlook. Therefore, the analyst should prioritize patching this vulnerability as soon as possible to prevent potential compromise of the workstations.

The document that was violated in this scenario is the SLA (Service Level Agreement). An SLA is a formal agreement between a service provider and a customer that defines the level of service expected. It includes specific metrics such as response times and resolution times. Missing an incident response deadline for customer 2 due to alerts from customer 1 indicates a breach of the agreed-upon service levels outlined in the SLA.

DNS exfiltration is a technique that uses the DNS protocol to transfer data from a compromised network or device to an attacker-controlled server. DNS exfiltration can bypass firewall rules and security products that do not inspect DNS traffic. The characteristics of the suspicious DNS traffic in the question match the indicators of DNS exfiltration, such as:

DNS traffic while a tunneling session is active: This implies that the DNS protocol is being used to create a covert channel for data transfer.

The mean time between queries is less than one second: This implies that the DNS queries are being sent at a high frequency to maximize the amount of data transferred.

The average query length exceeds 100 characters: This implies that the DNS queries are encoding large amounts of data in the subdomains or other fields of the DNS packets.

Official Reference:

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

https://resources.infosecinstitute.com/topic/bypassing-security-products-via-dns-data-exfiltration/

https://www.reddit.com/r/CompTIA/comments/nvjuzt/dns_exfiltration_explanation/