CS0-004 Exam Dumps - CompTIA Cybersecurity Analyst CySA+ V4 (New Version)

An after-action report (AAR) is the most comprehensive document associated with a closed incident because it consolidates the incident itself, the response activities performed, recovery actions, outcomes, deficiencies, and lessons identified during the event. NIST Cybersecurity Framework guidance specifically calls for preparing an after-action report that documents the incident, response and recovery activities, and lessons learned.

A lessons-learned document focuses primarily on what worked, what failed, and what should be improved. Those observations are important, but they represent only one component of a complete post-incident record. Root cause analysis has a narrower technical purpose: determining the fundamental condition that permitted the incident to occur or progress. A situation report is generally produced while an incident is ongoing to communicate current status, impact, actions, and outstanding issues.

An AAR is broader because it can incorporate the timeline, technical findings, containment and eradication actions, recovery results, stakeholder performance, root cause, lessons learned, and assigned corrective actions. NIST exercise guidance likewise treats lessons learned as information that becomes part of an after-action report.

Study Guide Reference: Reporting and Communication → Post-Incident Reporting → After-Action Reports → Lessons Learned → Root Cause Analysis → Corrective Actions.

The analyst should collect the Netstat output first because current network-connection information is highly volatile and will change immediately when the server is disconnected. netstat-type evidence can identify active TCP/UDP connections, listening services, remote endpoints, and potentially the communication channels associated with an attacker or command-and-control infrastructure.

Digital-forensic acquisition follows the order of volatility : evidence most likely to disappear or change should be captured before more persistent artifacts. RFC 3227 explicitly directs investigators to proceed from volatile to less-volatile evidence and identifies information such as routing data, ARP cache, process state, memory-related information, and network state as highly time-sensitive.

The ARP table is also volatile and should be captured early, but the wording “before disconnecting the server from the network” makes active connection state particularly important because those sessions will terminate when network connectivity is removed. ShellBags are persistent forensic artifacts stored within Windows Registry data and can be collected later from disk. A hard-disk image is critical but comparatively nonvolatile and should follow acquisition of live state.

Therefore, live network-session information takes priority.

Study Guide Reference: Incident Response and Management → Evidence Acquisition → Order of Volatility → Live Response → netstat → Network Connections → Forensic Preservation.

Compensating controls are appropriate when the preferred remediation cannot currently be implemented but the organization must still reduce exposure. A mission-critical system with an unpatched vulnerability for which no vendor patch exists is a classic example. The system cannot simply be removed from service because the business requires it, and conventional patching is unavailable.

The organization may therefore deploy alternative controls such as network segmentation, restrictive firewall rules, application allowlisting, disabling unnecessary services, enhanced monitoring, IPS signatures, access restrictions, or isolation of affected functionality. These measures do not eliminate the underlying defect; instead, they reduce the probability or impact of exploitation while a permanent solution is developed.

NIST's control framework is designed to allow security controls to be selected and tailored according to organizational mission requirements and risk, supporting the broader principle that organizations may apply appropriate alternative safeguards when operational constraints exist.

Option B requires no compensating control because remediation has already occurred. Option C describes a vulnerability that is not applicable to the organization's systems. Option D represents a false positive and therefore does not constitute an actual exposure requiring mitigation.

Study Guide Reference: Vulnerability Management → Mitigation → Compensating Controls → Patch Availability → Mission-Critical Systems → Segmentation and Monitoring.

192.168.76.5 — Patch; upgrade IIS to the current release

The correct remediation target is 192.168.76.5 , which is associated with an unsupported Microsoft IIS version and a CVSS score of 9.2 in the matching hotspot data. The remediation standard assigns vulnerabilities above 9.0 to the shortest remediation window, meaning the system requires action in seven days and therefore necessarily falls within the requested fourteen-day maximum. The corresponding remediation is to patch or upgrade IIS to a currently supported release .

The key vulnerability-management principle is that remediation priority is not determined exclusively by the existence of a vulnerability. Analysts must consider severity, asset context, exposure, business importance, exploitability, available remediation, and organizational service-level requirements. A product that has reached an unsupported state represents additional risk because standard security updates may no longer be supplied.

Upgrading the affected IIS installation directly removes the unsupported software condition rather than merely reducing exposure around it. A compensating control would be appropriate when remediation cannot immediately be performed, but it would not supersede a supported upgrade when that upgrade is operationally available.

Study Guide Reference: Vulnerability Management → Vulnerability Prioritization → CVSS → Remediation Timeframes → End-of-Life/Unsupported Software → Patching and Upgrading.

Clearly defined roles and responsibilities are foundational to incident-response preparation because responders must know in advance who has authority to make decisions and who performs specific technical, management, legal, communications, and recovery functions. Attempting to determine ownership while an active compromise is developing introduces delays, duplicated effort, communication failures, and potentially conflicting actions.

Preparation should define escalation paths, decision-making authority, contact mechanisms, incident leadership, technical responsibilities, evidence-management responsibilities, and coordination with business, legal, privacy, communications, and external parties where applicable. NIST's current incident-response guidance emphasizes preparation across organizational risk-management activities so organizations can respond and recover efficiently when incidents occur.

An after-action report is produced after an incident and documents the event, response actions, recovery, and lessons learned. Data-integrity validation is important during evidence analysis and recovery but is not the primary organizational foundation of preparation. Chain of custody must be established when evidence is collected and transferred, particularly where legal proceedings may occur, but it represents one procedure within a broader incident-response capability.

Without predefined ownership, even technically sound procedures may fail operationally.

Study Guide Reference: Incident Response and Management → Preparation → Incident Response Plan → Roles and Responsibilities → Escalation → Communication → Authority and Coordination.

Windows Security Event ID 4624 records a successful logon session. Therefore, querying the Security log for event 4624 provides the analyst with historical evidence of successful logins to the affected workstation.

Get-WinEvent is the appropriate PowerShell cmdlet for retrieving Windows event records. The FilterHashtable parameter allows efficient server-side filtering using attributes such as LogName and ID, rather than retrieving an entire event log and filtering the results afterward. Microsoft specifically documents LogName and ID as valid FilterHashtable keys and recommends this approach for efficient event-log querying.

The command then uses Sort-Object TimeCreated -Descending so the newest login events appear first, and Export-Csv preserves the resulting records for investigation.

Option A does not use the correct PowerShell event-query syntax shown. Options C and D search inappropriate log channels and unrelated event IDs. The evidence needed is authentication history, making the Windows Security log and successful-logon identifier 4624 the correct combination.

Study Guide Reference: Incident Response and Management → Evidence Collection → Windows Event Logs → PowerShell → Get-WinEvent → Security Event ID 4624 → Timeline Reconstruction.

Category 2 represents hosts whose RDP authentication characteristics indicate NTLM without Active Directory domain membership , making option C the correct interpretation. The Nmap command targets TCP port 3389 and executes RDP-related NSE scripts. Nmap's RDP scripts include rdp-ntlm-info, which obtains information through RDP services configured for CredSSP/Network Level Authentication, as well as rdp-enum-encryption, which evaluates supported RDP security layers and encryption.

Kerberos normally relies on a domain-based authentication infrastructure and a Key Distribution Center. A non-domain-joined workstation will typically rely on local authentication mechanisms and can use NTLM challenge-response authentication where appropriate. The absence of Active Directory domain characteristics, together with NTLM-specific RDP information, therefore distinguishes Category 2 from domain-integrated Kerberos authentication.

It is important operationally not to infer that every NTLM-capable system is necessarily outside Active Directory; domain members can fall back to NTLM under certain conditions. The examination conclusion depends on the combined evidence shown in the category output rather than NTLM alone.

Study Guide Reference: Vulnerability Management → Service Enumeration → Nmap NSE → RDP/3389 → NTLM → Kerberos → Active Directory Authentication Assessment.

The organization remains in the eradication phase because malicious artifacts are still being removed from affected systems and the environment has not yet reached a trusted state suitable for complete restoration. The phrase “removing malware from some of the affected hosts” indicates that responders are actively eliminating the threat across the compromised estate rather than merely observing or documenting it.

Eradication addresses malware, attacker persistence, exploited vulnerabilities, unauthorized accounts, malicious configurations, compromised credentials, and other mechanisms that could permit reinfection or renewed access. Only after responders have sufficiently eliminated those causes should affected resources progress fully into recovery and return to normal operation. NIST's current incident-response model identifies containment, eradication, and recovery as related but distinct activities and emphasizes restoring assets only after appropriate incident handling has occurred.

Detection would have occurred when the incident was initially discovered. Analysis determines scope, cause, and impact. Preparation takes place before incidents by establishing plans, tools, procedures, and capabilities. Post-incident activities occur after response and restoration and focus on organizational improvement.

The two-week duration does not determine the phase. The activity being performed does : continued removal of malware indicates eradication.

Study Guide Reference: Incident Response and Management → Containment → Eradication → Malware Removal → Persistence Removal → System Validation → Recovery.