What is Microsoft Sentinel

Microsoft Sentinel is a cloud-native Security Information and Event Management (SIEM) and Security Orchestration Automated Response (SOAR) solution provided by Microsoft. It is designed to provide enterprise-wide threat visibility, detection, response, and threat management across an organization’s digital estate. Here’s a short technical summary of its key features and capabilities:

1. Data Collection and Aggregation: Microsoft Sentinel seamlessly collects data at scale from users, devices, applications, and infrastructure, both on-premises and across multiple clouds. It supports a wide range of data sources, including Azure services, third-party cloud providers, and on-premises systems.
2. Advanced Threat Detection: Utilizing big data, machine learning technologies, and Microsoft’s vast threat intelligence, Sentinel can detect previously undetected threats and minimize false positives. It provides customizable detection rules and templates, allowing organizations to tailor detection to their environment.
3. Automated Incident Response: With its SOAR capabilities, Sentinel automates responses to identified threats, streamlining the incident response process. This includes automated playbooks that can be customized to perform specific actions, such as isolating compromised devices or notifying relevant personnel.
4. Visualization and Analysis Tools: Sentinel offers a range of tools for visualizing and analyzing security data. This includes customizable dashboards, interactive investigation graphs, and the ability to query data using Kusto Query Language (KQL), providing deep insights into security incidents and trends.
5. Integration and Collaboration: It integrates with a broad ecosystem of Microsoft and third-party security products, enhancing its detection and response capabilities. Sentinel also supports collaboration across security teams, offering shared workspaces and the ability to assign and track incidents.
6. Compliance and Security Standards: Microsoft Sentinel is built on Azure, which complies with major regulatory standards, ensuring that data is handled securely and in compliance with global and industry-specific regulations.
7. Cost Management and Scalability: Sentinel offers a flexible and scalable pricing model based on the volume of data ingested for analysis, making it accessible for organizations of all sizes. It leverages Azure’s scalable infrastructure to efficiently handle large volumes of data without the need for additional on-premises infrastructure.

In summary, Microsoft Sentinel provides organizations with a comprehensive and integrated SIEM and SOAR solution, offering advanced threat detection, automated incident response, and extensive data analysis capabilities. It helps businesses manage their security posture more effectively, respond to incidents rapidly, and reduce overall security risks.

The Basics of Microsoft Sentinel

Data Connectors

To begin utilizing Microsoft Sentinel, the initial step involves linking your data sources to the platform.

Microsoft Sentinel offers a wide array of built-in connectors, particularly for Microsoft-based solutions, facilitating immediate and seamless real-time integration. These connectors encompass a variety of Microsoft resources, such as Microsoft Defender XDR, Microsoft Defender for Cloud, Office 365, Microsoft Defender for IoT, among others.

Additionally, it supports integration with Azure services through connectors for Microsoft Entra ID, Azure Activity, Azure Storage, Azure Key Vault, Azure Kubernetes Service, and others.

For integration with external security and application ecosystems beyond Microsoft’s offerings, Microsoft Sentinel provides specialized connectors. It also allows for the connection of your data sources using common event formats, Syslog, or REST-APIs, broadening its compatibility and integration capabilities.

Workbooks

Once you’ve set up Microsoft Sentinel, you can oversee your data through its integration with Azure Monitor workbooks.

While workbooks might appear different in Microsoft Sentinel compared to Azure Monitor, understanding how to craft a workbook in Azure Monitor can still be beneficial. Microsoft Sentinel enables the creation of custom workbooks tailored to your data needs. Furthermore, it includes pre-designed workbook templates, empowering you to immediately derive valuable insights from your data upon connecting a source.

Analytics Rules

To streamline your workflow and decrease the volume of alerts requiring your attention, Microsoft Sentinel leverages analytics to consolidate related alerts into incidents. An incident represents a collection of related alerts that, when combined, suggest a potentially actionable threat for investigation and resolution. You can utilize the default correlation rules as provided or adapt them as a foundation for crafting personalized ones. Moreover, Microsoft Sentinel offers machine learning-based rules designed to understand your network’s typical behavior patterns and identify anomalies across your resources. This analytical approach enhances threat detection by merging low fidelity alerts pertaining to various entities into cohesive, high-fidelity security incidents, thereby clarifying and prioritizing potential threats.

Playbooks

Simplify the orchestration of your security operations and automate routine tasks with playbooks that integrate seamlessly with Azure services and the tools you already use.

The automation and orchestration capabilities of Microsoft Sentinel are built on a highly adaptable architecture, ensuring your ability to automate at scale in response to emerging technologies and threats. Through Azure Logic Apps, Sentinel empowers you to create playbooks using an extensive collection of connectors, numbering in the hundreds, for a wide array of services and systems. These connectors facilitate the incorporation of bespoke logic into your operational workflows, covering options such as:

• ServiceNow
• Jira
• Zendesk
• HTTP requests
• Microsoft Teams
• Slack
• Microsoft Entra ID
• Microsoft Defender for Endpoint
• Microsoft Defender for Cloud Apps

For instance, if your processes involve the ServiceNow ticketing platform, you can configure Azure Logic Apps to automatically initiate ServiceNow tickets in response to specific alerts or incidents, thereby streamlining and enhancing the efficiency of your security response mechanism.

Hunting

Leverage the robust hunting capabilities of Microsoft Sentinel, which are grounded in the MITRE ATT&CK framework, to proactively seek out security threats within your organization’s data sources before they trigger alerts. These powerful search-and-query tools empower you to tailor custom detection rules based on your investigative queries, allowing you to elevate those findings to alerts for your security incident response team.

During your threat hunting activities, you can mark significant events using bookmarks, enabling easy revisitation of noteworthy findings. Bookmarks not only facilitate personal reference but also allow for the sharing of events with team members. Moreover, you can aggregate these marked events with related incidents, assembling a comprehensive case for in-depth investigation, thereby enhancing your organization’s proactive defense posture.

Alerts vs Incidents

In Microsoft Sentinel, “alerts” and “incidents” are closely related but serve different roles in the context of security event management and response. Here’s a breakdown of the differences:

Alerts

• Definition: Alerts are notifications about events or conditions that might indicate a security issue or threat. They are typically generated by detection rules that analyze the data streaming into Microsoft Sentinel from various sources.
• Granularity: An alert is often granular, focusing on a single event or a small set of events that match specific criteria. It may indicate something suspicious, but not necessarily a confirmed threat.
• Source: Alerts can be triggered by a variety of sources, including analytics rules, threat intelligence, Microsoft and non-Microsoft security products, and custom detection rules.

Incidents

• Definition: Incidents are aggregates of one or more related alerts that, together, represent a potential security issue or confirmed threat that requires investigation and response. Incidents are designed to help security teams focus on threats that need attention by grouping related alerts into a single entity.
• Context and Correlation: The creation of an incident involves correlating related alerts based on factors like timing, attack techniques, threat actors, and affected assets. This correlation provides more context and helps in understanding the scope and impact of the threat.
• Management and Investigation: Incidents are the primary entities that security analysts interact with during the investigation and response process. They enable a structured approach to triaging, investigating, and remediating threats. Analysts can assign incidents, add tags for organization, and track the investigation status.

In summary, while alerts are the individual pieces of evidence that might indicate suspicious activity or security threats, incidents are more comprehensive entities that group related alerts to provide a clearer picture of a security issue, facilitating more effective investigation and response by security teams.

Please keep following this Blogseries about Microsoft Sentinel! In the next episode we will guide you trough the initial basic setup of Microsoft Sentinel!