Optimizing Splunk Enterprise Security for your SOC

Splunk Enterprise Security dashboard matrix

The Splunk Enterprise Security dashboard matrix is a comprehensive reference tool that provides an overview of the dashboards available in ES and their corresponding data model requirements. By linking data model names to their respective Common Information Model (CIM) documentation, users can quickly access details like tags, field names, and field values needed for CIM compliance.

This matrix helps security analysts and administrators identify which data models support specific dashboards and panels within ES. It’s particularly useful for troubleshooting missing data in dashboard panels, as it helps pinpoint which data models are being used and investigate potential causes for data gaps, such as improper data normalization or missing inputs.

In Splunk Enterprise Security 8.3, performance optimizations in the Analyst Queue, a core component of the integrated Splunk Mission Control, continues to enhance dashboard usability. With faster load times and improved filtering options, analysts can access and investigate data more efficiently, ensuring that no critical information is missed.

Common Information Model overview

The Splunk Common Information Model (CIM) is a standardized framework designed to work with normalized data from diverse sources within the Splunk platform. It provides consistent structure and naming conventions, enabling meaningful insights across varied datasets. The CIM consists of predefined data models that cover domains like network traffic, server operations, and authentication processes.

Adhering to the CIM allows users to leverage pre-built dashboards, reports, and apps that expect data in CIM format, ensuring seamless integration between different Splunk apps. This standardization is critical for ES and other security applications reliant on normalized data for effective threat detection and analysis.

Splunk Enterprise Security 8.3 continues to enhance tagging and metadata support in the CIM to improve the efficiency of finding-based detections. These refinements allow better event correlation and grouping, providing analysts with actionable insights while minimizing noise.

Additionally, ES 8.3’s alignment with the Open Cybersecurity Schema Framework (OCSF) standards promotes a common, vendor-agnostic data schema, which streamlines the normalization of security telemetry and enhances interoperability across diverse security tools. This OCSF alignment complements the CIM by providing a standardized way to ingest and map data, improving the fidelity of correlation searches and risk-based alerting, crucial for a Premier SOC.

Event breaking: LINE_BREAKER and EVENT_BREAKER

Correctly configured event breaking leads to more accurate and reliable search results, better event correlation and analysis in security investigations, and enhanced fidelity with ES findings. Proper event breaking ensures that each security event is correctly parsed as a complete unit, event timestamps are accurately extracted and indexed, and no critical information is truncated or split across multiple events. This is an on-going process that is key in data on-boarding and normalization for all Splunk events.

LINE_BREAKER and EVENT_BREAKER are both important configurations for determining event boundaries, but they serve different purposes. LINE_BREAKER is a props.conf setting that defines how the Splunk platform splits the incoming data stream into separate lines during the initial parsing phase. It uses a regular expression, typically looking for newline or carriage return characters. EVENT_BREAKER, on the other hand, is used specifically by universal forwarders to determine event boundaries when forwarding data. While LINE_BREAKER is applied at the indexer level, EVENT_BREAKER allows the forwarder to identify complete events and efficiently distribute them across multiple indexers or backend servers.

To use these correctly:

1. Use LINE_BREAKER with SHOULD_LINEMERGE=true.
2. Configure EVENT_BREAKER_ENABLE=true and align EVENT_BREAKER with LINE_BREAKER on universal forwarders.
3. Adjust TRUNCATE settings to accommodate larger security events.
4. Review and update settings regularly as new data sources are added.

Splunk Enterprise Security 8.3 continues to support advanced detection workflows that rely on accurately parsed events. To fully leverage the improved detection capabilities in ES 8.3, ensure proper alignment of LINE_BREAKER and EVENT_BREAKER configurations with your data sources.

Index-time and search-time field extractions

Index-time and search-time field extractions in the Splunk platform differ in when and how they process data. Index-time extractions occur as data is being indexed, extracting fields like host, source, and source type by default. While index-time extractions can improve search performance for frequently used fields, they can also slow down the indexing process and increase index size. Search-time extractions, on the other hand, occur when a search is executed, allowing for more flexibility in field creation and modification without reindexing data. Generally, search-time extractions are recommended for most use cases due to their flexibility and minimal impact on indexing performance.

In Splunk Enterprise Security 8.3, optimized indexer resource utilization ensures that even large-scale deployments experience improved performance during indexing and search operations, particularly for environments with high data ingestion or complex detection rules.

The introduction of ingest actions in Splunk platform 9+ provides an even earlier opportunity for data manipulation. This feature allows for filtering, masking, and routing data directly at the point of ingestion, reducing the volume of data sent to indexers and optimizing license usage, a key capability for Premier data management.

Tags and search constraints for data model acceleration

Tags play a crucial role within the Common Information Model by providing a way to categorize and normalize data across different sources. Tags are metadata labels that can be applied to fields, allowing for consistent classification of data regardless of the original source format. In the context of the CIM, tags help map vendor-specific field names to standardized CIM field names, enabling unified analysis across diverse data sources. This tagging system is fundamental to the CIM's goal of providing a standardized framework for data interpretation and analysis within the Splunk platform. It facilitates easier correlation of events, improved interoperability between Splunk apps, and more efficient development of dashboards and reports.

Splunk Enterprise Security 8.3 introduces additional metadata fields and improved logic for grouping findings, making detection workflows more effective for complex environments. These updates further enhance the value of tagging within the CIM, enabling better event correlation and faster threat detection.

Data enrichment

Data enrichment in Splunk Enterprise Security adds contextual information to events, enhancing their value for security analysis and response. ES uses various methods to enrich data, including the assets and identities framework, which correlates asset and identity information with events to provide additional context. This framework takes data from external authoritative platforms to populate lookups, which ES then correlates across datasets at search time, addressing issues such as overlapping address spaces and improving scalability.

Enrichment in ES can be achieved through multiple means, including:

• Threat intelligence feeds
• Common Information Model (CIM) for standardization
• Lookup tables for additional context

The goal of enrichment is to provide SOC analysts with critical information quickly, aiding in faster and more effective threat detection and response. By enriching data with details like IP geolocation, user information, or threat intelligence, ES enables analysts to gain a more comprehensive understanding of security events, ultimately reducing mean time to respond (MTTR) and improving overall security operations efficiency.

Splunk Enterprise Security 8.3 improves asset and identity correlation workflows, making it easier to analyze enriched data directly in the updated Analyst Queue. These enhancements help SOC teams gain a more comprehensive understanding of security events and respond more effectively.

Asset and identity data

Splunk Enterprise Security uses asset and identity data to enrich events at search time, providing crucial context for security analysis and response. When asset and identity correlation is enabled, ES compares indexed events with asset and identity information stored in lookup tables. It matches fields like src, dest, dvc, user, and src_user against the asset and identity lists, looking for corresponding IP addresses, MAC addresses, DNS names, Windows NetBIOS names, or user identities. When a match is found, ES adds relevant contextual information to the event, such as whether an asset is expected, and its priority, owner, business unit, and other attributes. This enrichment process allows analysts to quickly understand the significance of security events, correlate multiple events related to the same asset or identity, and make more informed decisions during incident investigation and response.

Configuring users and roles

Splunk Enterprise Security uses role-based access control (RBAC) to carefully define and assign roles so that an administrator can control what actions users can perform, what day they can access systems, and what capability they possess within the application. The granular level of control not only enhances security by adhering to the principal of least privilege, but also allows for more efficient operations by tailoring access-based job responsibilities and organizational needs.

Proper user and role configuration in ES also ensures compliance with regulatory requirements and internal security policies. Custom roles inherit from default roles, leveraging function-specific specific capabilities to help organizations find the balance between security and operational efficiency. This approach allows the segregation of duties to ensure that users only have access to the resources necessary for their job function, and provides a clear audit trail of user activities. Additionally, well-defined roles and permissions contribute to a streamlined onboarding process for new employees, making it easier to manage changes as responsibilities evolve.

Risk-based alerting (RBA)

Some key tips for implementing effective RBA processes include:

• Ensure your data models are properly accelerated, and that you’re using the correct indexes to feed appropriate data into them.
• Begin a focused approach by activating only a few key detections in QA mode, allowing you the time to test and adjust without impacting your production environment.
• As you develop your RBA strategy, concentrate on identifying and removing noise from the risk index to increase alert fidelity.
• Take advantage of the required fields for entity and risk score modifiers in findings and intermediate findings to improve risk calculations.
• Utilize the optimize risk incident rules for better performance and explore the preview feature for an easier, SPL-free approach to manage and aggregate risk.
• Continuously monitor and adjust your risk scores and thresholds based on your environment specific needs.
• Consider implementing custom risk rules that analyze risk events over longer periods to detect subtle, long-term threats.

In Splunk Enterprise Security 8.3, refinements to risk incident rules improve detection fidelity and allow analysts to focus on high-confidence alerts. The updated workflows also include guidance for leveraging intermediate findings to create actionable detection outputs.

RBA in ES 8.3 also offers enhanced prioritization of security threats in a manner that adapts to the MITRE ATT&CK framework and entity risk scores, a critical capability for a Premier SOC to combat alert fatigue and prioritize effectively.

Health checklist

Ongoing checks for the health of Splunk Enterprise Security should include:

• Uninstall unnecessary add-ons.
• Tune artificial limits.
• Profile search slots and skipped searches using the monitoring console.
• Optimize long-running searches.
• If you experience skipped searches, consider rescheduling your searches on a more even schedule.
• Balance your data.
• Upgrade the Splunk platform.
• Watch your bundle size.
• Tune your data models (indexes, and potentially also backfill range).
• If necessary, make your lookups smaller.

Incident management

The unified work surface in Splunk Enterprise Security 8.x (including 8.3) integrates detection, investigation, and response workflows into a single modern interface, largely through the native integration of Splunk Mission Control. With this consolidation, analysts can detect, investigate, and respond to threats without leaving ES, significantly improving operational efficiency with one-click access to automation and orchestration tasks that streamline the incident response process.

Additionally, ES 8.3 introduced enhanced detections and a risk-based alerting strategy empowering analysts to focus on critical incidents, creating high-confidence aggregated alerts for investigations. The new taxonomy aligns with the Open Cyber Security Framework (OCSF), simplifying terminology across workflows and breaking down data silos that impede threat detection. Leveraging response plans allows for easy collaboration execution of incident response workflows for common security use cases with the ability to assign key stakeholders to specific phases and apply automation playbook for quicker remediation.

Splunk Enterprise Security 8.3 further enhances this integration with improved Splunk Mission Control workflows, enabling smoother collaboration during cross-team investigations. Analysts can now manage cases with greater efficiency, taking advantage of enhanced case management capabilities introduced in this version.

Analyst Queue

The Analyst Queue serves as the primary operational hub within Splunk Mission Control for security analysts, providing a centralized view of all security findings and incidents that require attention. It's designed to streamline an analyst's daily workflow by presenting prioritized alerts and allowing for efficient triage and investigation.

Splunk Enterprise Security 8.3 introduces performance optimizations for the Analyst Queue, including faster load times and enhanced filtering options. These improvements ensure that analysts can quickly access and prioritize investigations, reducing the time spent on routine tasks.

The Analyst Queue also features an enhanced side panel for detailed information, allowing analysts to add notes with text, attachments, images, and URLs to investigations, and run playbooks directly. This streamlined experience is a hallmark of the Premier offering, making advanced capabilities accessible to all SOC analysts by providing a clear, actionable interface to manage their workload, collaborate with peers, and initiate automated responses.

Threat intelligence

With the active integration of Cisco Talos, threat intelligence security teams can now access enhanced threat intelligence across Splunk Attack Analyzer, Splunk Enterprise Security, and Splunk SOAR. This integration helps streamline threat detection and response processes by reducing alert fatigue and allowing security analysts to focus on critical threats.

For Splunk ES 8.3, the Cisco Talos Intelligence enriches findings, providing context like threat level and category. For Splunk SOAR, a dedicated connector automates the analysis of URL, domain, and IP reputations. Splunk Attack Analyzer globally integrates Talos intelligence to enrich URLs in the attack chain. This comprehensive, real-time threat intelligence is a cornerstone of a Premier SOC's proactive defense strategy.

Use case development and response plans

Response plans in Splunk Enterprise Security allow users to easily collaborate and execute incident response workflows for common security use cases. Response plan templates allow users to see each phase of an incident response plan, assign key stakeholders to specific phases, and apply simple automation playbooks to tasks for rapid remediation.

Developing use cases and response plans should include discussion of all the required logistics for realization of prescribed use cases and response plans. Response plans should be developed in parallel with use case development.

When developing use cases, ensure you account for:

• Applicable data sources
• Onboarding method
• Dependencies (architecture, hardware components, etc.)
• Data or system owner
• Number of dependent use cases
• Response plan supporting

When developing response plans, ensure you account for:

• Required inputs
• Required integrations
• Asset owners
• Dependencies (credentials, architecture, etc.)
• Number of dependent actions
• Response implementation plan based on priority roadmap

Splunk Enterprise Security 8.3 now features native Splunk SOAR integration, enabling unified orchestration and automation directly within the ES environment, whether the SOAR deployment is on-premises or cloud-based. This robust integration is a key component of the Premier experience, allowing for seamless execution of automated response workflows. Splunk SOAR 7.0.0 (On-premises, released September 18, 2025) further enhances playbook development with features like Python 3.13 support, IPv6 support, and improved visual playbook editor capabilities such as copying and pasting blocks, and guided automation with Data Preview. These advanced SOAR capabilities are directly leveraged by ES 8.3 for a Premier automated response.

Detection authoring

Splunk Enterprise Security 8.x offers editors for event-based and finding-based detections, with advanced versioning and rollback capabilities.

Splunk Enterprise Security 8.3 builds on these capabilities with refinements to finding-based detections, improving the accuracy and efficiency of grouping findings into finding groups. These updates allow security teams to develop high-fidelity detections tailored to their specific environments.

The ability to save new versions and roll back to prior versions of detections with a single click significantly improves detection hygiene and content management, a critical aspect for Premier detection engineering. Additionally, the AI Assistant for Splunk Enterprise Security introduced in ES 8.2.0 provides Premier capabilities to summarize findings, generate SPL searches, and create investigation reports, accelerating the detection authoring and investigation process.

Proactive insider threat detection with native UEBA in ES Premier

A Premier SOC needs to proactively identify and mitigate insider threats, compromised accounts, and lateral movement that traditional SIEM rules might miss due to their "low and slow" nature or sophisticated evasion techniques. This requires analyzing user behavior over time for anomalies.

With native UEBA embedded in Splunk Enterprise Security Premier, the SOC gains advanced behavioral analytics capabilities. Instead of relying solely on predefined rules, UEBA continuously baselines normal user and entity behavior (for example, login patterns, data access, application usage, or network activity). When a user (for example, a disgruntled employee or a compromised account) deviates significantly from their established baseline, such as accessing sensitive data outside of working hours, logging in from an unusual geographical location, or attempting to access systems they've never touched before, UEBA generates high-fidelity anomalies.

These anomalies are automatically correlated with other security events within ES 8.3, contributing to an entity's risk score. If the aggregate risk score crosses a predefined threshold, a finding is generated in the Analyst Queue. A Splunk SOAR 7.0.0 playbook, triggered by this high-risk finding, can then automatically initiate a response: isolating the user's endpoint, revoking temporary access, notifying the incident response team via chat, and creating a detailed case in Splunk Mission Control for further human investigation. This proactive, AI-driven approach, accessible to every SOC analyst through Premier, significantly enhances the SOC's ability to detect and respond to complex insider threats and compromised accounts, reducing the mean time to detect (MTTD) and mean time to respond (MTTR) for critical, subtle threats.

Pre ES 7.3 upgrade caveats and deprecations