Splunk SPLK-5001 - Splunk Certified Cybersecurity Defense Analyst

Tacticsare the overarching objectives or strategies attackers use during their operations, whiletechniquesare the specific methods used to achieve these tactics. In this case,gathering information about a target(often referred to as Reconnaissance) is atacticbecause it represents a high-level objective of understanding the target. The other options provided (persistence, phishing, privilege escalation) are specifictechniquesused to achieve the broader goals or tactics.

TheContinuous Monitoringcycle begins with theDefine and Predictphase, where the security team establishes what needs to be monitored (defining assets, risks, controls) and predicts potential threats and vulnerabilities. This foundational phase sets objectives and scope for the monitoring program.

Subsequent phases likeMonitor and Protect,Assess and Evaluate, andRespond and Recoverfollow the initial definition.

This phased approach aligns with frameworks such as NIST’s Risk Management Framework and Continuous Monitoring guidelines.

Splunk’s cybersecurity documentation highlights the importance of this first phase for establishing a proactive and informed security posture.

The Lockheed Martin Cyber Kill Chain® is a widely recognized framework that breaks down the stages of a cyber attack. The stages are: Reconnaissance, Weaponization, Delivery, Exploitation, Installation, Command and Control (C2), and Actions on Objectives. The scenario described—modifying the registry on a compromised Windows system to ensure malware runs at boot time—fits into theInstallationphase. This phase involves placing a persistent backdoor or other malicious software on the victim's system, ensuring it can be executed again, even after a system reboot. By modifying the registry, the attacker is achieving persistence, a classic example of the Installation phase.

Continuous Monitoring Cycle:This cycle is part of a broader security strategy that involves constantly assessing and managing the security state of an organization's information systems. The phases generally include defining metrics, collecting data, analyzing it, reporting findings, and implementing improvements.

Analyze and Report Phase:

Data Evaluation:In this phase, the data collected from various monitoring tools and sensors is thoroughly analyzed. Security analysts look for trends, anomalies, and indications of potential threats or vulnerabilities.

Reporting:After the analysis, a report is generated that highlights the findings, including any detected issues, their potential impact, and the current effectiveness of security measures.

Recommendations:Based on the analysis, the report usually includes suggestions for improvements, such as additional security controls, configuration changes, or policy updates. These recommendations are aimed at enhancing the organization's security posture and addressing any identified gaps or weaknesses.

Purpose of Recommendations:The goal of this phase is to ensure that the organization’s security measures are continuously improved based on the latest data and threat landscape. It is a critical step in maintaining an effective security program that adapts to new challenges.

Unusual Traffic Patterns:

The key observation here is that one of the servers is sending out a significantly large amount of data to a single external system, with no corresponding increase in incoming traffic.

Possible Threat Activities:

A. Data Exfiltration:

This scenario typically aligns with data exfiltration, where an attacker has successfully compromised a system and is sending out large volumes of stolen data to an external server.

Data exfiltration often involves consistent or large data transfers over time to an external IP address, which matches the description provided.

B. Network Reconnaissance:

While reconnaissance involves scanning and probing, it generally does not produce large outbound data flows but rather small, frequent connection attempts or queries.

C. Data Infiltration:

Infiltration would involve incoming data to the compromised server, which contradicts the scenario as there is no observed increase in incoming traffic.

D. Lateral Movement:

Lateral movement would involve traffic between internal systems rather than large amounts of data being sent to an external system.

Scenario Analysis:Conclusion:Given the evidence of large data transfers to a single external system without corresponding inbound traffic,data exfiltrationis the most likely scenario. This suggests that an adversary has compromised the server and is extracting valuable or sensitive data from the organization.

In theSplunk Common Information Model (CIM), the Authentication Data Model defines standardized field names to normalize data from various sources. For privilege escalation events, the user who initiates the escalation (i.e., the actor performing the elevated action) is represented by the fieldsrc_user. This field captures the source or originating user account involved in the authentication event.

src_user: Typically refers to the user who initiated the action, such as the account escalating privileges.

dest_user: Refers to the target user account involved, such as the user being impersonated or the elevated account.

src_user_idandusernameare either deprecated or less precise in CIM for privilege escalation contexts.

TheSplunk CIM documentation(specifically the Authentication Data Model section) states thatsrc_useris the correct normalized field to capture the initiating user in escalation or impersonation events, supporting consistent searches, alerts, and dashboards across varied log sources.

In Splunk, therarecommand is used to return the least common values in a field. This command is particularly useful for anomaly detection, as it helps identify unusual or infrequent occurrences in a dataset, which may indicate potential security issues.

rare Command:

This command works by identifying values that appear infrequently within a specified field. It’s a powerful tool for Cyber Defense Analysts who are looking for anomalies that could signify malicious activities.

Incorrect Options:

A. least:This is not a valid Splunk command.

B. uncommon:This is not a valid Splunk command.

D. base:This is not a relevant command for finding the least common values.

Tactical intelligenceprovides insights into the specific behaviors, tools, and techniques used by threat actors. When a Cyber Threat Intelligence (CTI) team produces a report detailing a threat actor’s typical behaviors and intent, they are delivering tactical intelligence. This type of intelligence is actionable and directly supports defenders in identifying, mitigating, and responding to threats in a timely manner.

Tactical Intelligence:

Focuses on the specific, detailed activities of threat actors, such as the Tactics, Techniques, and Procedures (TTPs) they employ.

This intelligence helps in creating defensive strategies, such as refining detection rules, improving incident response plans, and enhancing threat hunting efforts.

Incorrect Options:

A. Operational:Operational intelligence involves real-time information and insights that support ongoing operations, often within a narrow timeframe.

B. Executive:Executive intelligence is high-level and strategic, intended for decision-makers and typically involves summaries rather than detailed technical information.

D. Strategic:Strategic intelligence is long-term and broad in scope, focusing on overall trends and the geopolitical context, rather than specific TTPs.

The main difference between hypothesis-driven and data-driven threat hunting lies in the approach. Inhypothesis-drivenhunting, the hunter starts with a theory or hypothesis about what kind of malicious activity might be occurring and then searches the data to confirm or refute that hypothesis. On the other hand,data-drivenhunting involves sifting through existing datasets to uncover patterns, anomalies, or activities that were not initially suspected. Hypothesis-driven approaches are more focused and often guided by threat intelligence or knowledge of attacker behaviors, while data-driven approaches rely on broad data analysis to identify unexpected threats.

TheTERM()search command in Splunk allows an analyst to match a specific term exactly as it appears, even if it contains characters that are usually considered minor breakers, such as periods or underscores. By usingTERM(), the search engine treats everything inside the parentheses as a single term, which is especially useful for searching log data where certain values (like IP addresses or filenames) should be matched exactly as they appear in the logs.