Own the CS0-003: CySA+ Prep That’s Built for Real-World SOC Analysts

The best priority based on common attack frameworks for a new program to reduce attack surface risks and threats as part of a zero trust approach is to reduce the administrator and privileged access accounts. Administrator and privileged access accounts are accounts that have elevated permissions or capabilities to perform sensitive or critical tasks on systems or networks, such as installing software, changing configurations, accessing data, or granting access. Reducing the administrator and privileged access accounts can help minimize the attack surface, as it can limit the number of potential targets orentry points for attackers, as well as reduce the impact or damage of an attack if an account is compromised.

The one-liner script is utilizing JavaScript to execute a PowerShell command that downloads and runs a script from an external source, indicating the use of custom malware to download an additional script. References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 4: Security Operations and Monitoring, page 156.

Thegoal of forensic analysisin a post-incident scenario is to identify theroot causeof the incident. This helps prevent future occurrences and enhances the security posture of the organization​.

Option A (Full picture of risks)is more aligned with a risk assessment rather than forensic analysis.

Option B (Notifying law enforcement)depends on the situation, but forensic analysis is performed even when legal action is not involved.

Option C (Further containment)is part of incident response, but forensic analysis happensaftercontainment.

Thus,D is the correct answer, asdetermining root cause is the key objective of forensic analysis​.

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.

Vulnerability 2 should be prioritized as it is exploitable, has high exploit activity, and is exposed externally according to the SMITTEN metric. References: Vulnerability Management Metrics: 5 Metrics to Start Measuring in Your Program, Section: Vulnerability Severity.

The correct answer is D because random-looking DNS requests can indicate malware using a domain generation algorithm (DGA) for command-and-control, but the analyst should first validate the suspicious domains using threat intelligence or reputation sources. The scenario asks what should be done first to determine whether Host X has been compromised, so enrichment and validation of the domain indicators is the best first step.

Exact supporting extract: the All-in-One CySA+ guide explains that malware may use DGAs for command-and-control exchanges and that high-entropy domains often look like gibberish to humans. It also warns that DGAs may have legitimate uses in content delivery networks, so additional analysis is needed to reduce false positives.

The same guide defines a DGA as a threat actor technique used to generate domain names rapidly using seemingly random but predictable processes so malware can eventually connect with command-and-control infrastructure.

Why the other options are incorrect:

A is incorrect because allowing the domains before validation may permit command-and-control or data exfiltration.

B is incorrect because reinstalling the software does not determine whether the DNS domains are malicious or legitimate.

C is incorrect because blocking all outbound connections is a containment action, not the best first investigative step.

D is correct because threat intelligence helps validate whether the suspicious domains are known malicious infrastructure or legitimate generated domains.

A Memorandum of Understanding (MOU) is a formal agreement that outlines the roles and responsibilities of each party involved in a particular process or project, especially within security frameworks. In the context of cybersecurity, an MOU is commonly used to clarify and document the security responsibilities of different departments or entities involved. It helps ensure everyone understands their specific duties and contributions to security, which is crucial for coordination and risk management. According to CompTIA Security+ guidelines, while options A, C, and D describe other forms of agreements, they do not capture the essential purpose of an MOU as accurately as option B does.

A “network data closet” attack is a physical-environment incident (hardware, cabling, physical access/tampering). Proper documentation in such cases includes documenting the scene and physical state of impacted items so that investigators can reconstruct what was present, what was changed, and how things were connected.

The All-in-One CySA+ guide explicitly states that an important step is documenting the physical environment and that an easy way is to take lots of photos of the scene:

Exact extract (All-in-One Exam Guide):

“Another important… step is to document the entire physical environment around a device. An easy way to do this is to take lots of photos of the scene.”

Why the other options are less correct:

A is a recovery/ops task, not primary incident documentation of a physical attack scene.

B may be useful in some contexts, but the best practice for a physical incident scene is to photograph impacted items and surroundings.

C can help later, but it’s not the first/best documentation action for a physical tampering incident compared to capturing the scene as-found.

The first step that should be performed when establishing a disaster recovery plan is to agree on the goals and objectives of the plan. The goals and objectives of the plan should define what the plan aims to achieve, such as minimizing downtime, restoring critical functions, ensuring data integrity, or meeting compliance requirements. The goals and objectives of the plan should also be aligned with the business needs and priorities of the organization and be measurable and achievable.

Reverse engineering is a technique that involves analyzing a binary file to understand its structure, functionality, and behavior. Reverse engineering can help security analysts perform malware analysis, vulnerability research, exploit development, and software debugging. Reverse engineering can be done using various tools, such as disassemblers, debuggers, decompilers, and hex editors.