Tutorial / Cram Notes
They enable security analysts to detect and respond to threats that may bypass standard detection methods. The Microsoft Security Operations Analyst SC-200 certification exam tests a candidate’s ability to create and manage these custom detection rules and alerts within Microsoft security solutions like Microsoft 365 Defender and Azure Sentinel.
Understanding Custom Detections
Custom detections are user-defined rules that generate alerts when specific patterns of activity or behavior that may indicate a threat are identified in the data sources being monitored. These rules can be based on various signals, such as log files, network data, and user behaviors.
Configuring Custom Alerts in Microsoft 365 Defender
Microsoft 365 Defender allows the creation of custom alert rules to tailor detection to specific organizational needs.
Step-by-Step Process:
- Access Microsoft 365 Defender: Navigate to the Microsoft 365 Defender portal.
- Navigate to ‘Alerts’: Go to the ‘Alerts’ section and select ‘Advanced hunting’.
- Query Creation: Use the Kusto Query Language (KQL) to create complex queries looking for specific indicators of compromise or unusual activities.
- Alert Rule Creation: Convert the query into an alert detection rule by defining parameters such as severity levels, alert titles, and response actions.
- Alert Configuration: Configure alert settings like aggregation, suppression, and scheduling.
- Testing: Test the rule to validate its effectiveness before deployment.
- Deployment: Deploy the rule so that it actively monitors for the defined activities.
- Review and Maintenance: Regularly review and update the custom detection rule to ensure it remains effective.
Custom Detections in Azure Sentinel
Azure Sentinel provides an even more advanced set of tools for creating, managing, and deploying custom detection rules.
Steps include:
- Access Azure Sentinel: Open the Azure Portal and navigate to the Azure Sentinel service.
- Access Analytics: In the Azure Sentinel workspace, go to ‘Configuration’ and select ‘Analytics’.
- New Rule Template: Choose to create a new rule or use an existing template.
- Use KQL for Rule Logic: Define the custom rule logic using KQL to identify specific behaviors or patterns.
- Set Rule Parameters: Configure the rule with the necessary parameters, like rule frequency, event grouping, and trigger thresholds.
- Response Automation: Pair the rule with automated response actions such as playbooks (Azure Logic Apps) for orchestration.
- Enable Rule: Turn on the rule to begin monitoring data streams for the defined patterns.
- Validation and Tuning: Continuously validate the effectiveness of the rule and adjust its logic to reduce false positives and tune detections.
Differences Between Microsoft 365 Defender and Azure Sentinel Custom Detections
| Feature | Microsoft 365 Defender | Azure Sentinel |
|---|---|---|
| Query Language | KQL | KQL |
| Response Actions | Predefined actions | Playbooks (Azure Logic Apps) |
| Data Sources | Microsoft 365 data | Multiple, including third-party |
| Rule Testing | Alert rule test feature | Rule logic test environment |
| Integration | Microsoft 365 suite | Broad (various data connectors) |
| Advanced Analytics | Limited compared to Sentinel | Advanced ML and AI capabilities |
Best Practices for Managing Custom Detections and Alerts
- Regularly Update Rules: Threats evolve, so regularly update your custom detection rules to adapt to the latest threat landscape.
- Reduce False Positives: Continuously monitor the performance of your custom alerts to reduce false positives, which waste valuable resources.
- Leverage Threat Intelligence: Incorporate threat intelligence into your customs rules to enhance detection capabilities.
- Automate Responses: Where possible, automate responses to accelerate mitigation and allow analysts to focus on more strategic tasks.
In conclusion, configuring and managing custom detections and alerts is an essential skill for a Security Operations Analyst. It ensures that an organization can respond to new and emerging threats, tailoring detection mechanisms to the specific landscape of its IT environment. Moreover, mastering the use of Kusto Query Language and the ability to adapt and tune custom rules is a defining trait of an effective analyst, crucial for success in the SC-200 Microsoft Security Operations Analyst exam.
Practice Test with Explanation
True or False: The only way to create custom detections in Microsoft Sentinel is by using Kusto Query Language (KQL).
- Answer: False
Explanation: While KQL is widely used for creating custom detections, Microsoft Sentinel also allows the use of other tools such as built-in templates and Microsoft Sentinel notebooks to create custom rules.
Multiple Select: What can you configure as part of a custom alert rule in Microsoft Sentinel? (Select all that apply)
- A) Schedule
- B) Severity
- C) Trigger actions
- D) Data source
Answer: A, B, C
Explanation: When configuring a custom alert rule, you can set the schedule for how often the rule runs, define the severity of the alert, and configure what actions should be triggered when the alert fires. Data sources are not configurable as part of the rule since they are predefined based on the log data.
True or False: Microsoft 365 Defender and Azure Defender alerts can be integrated into Microsoft Sentinel without any additional configuration.
- Answer: False
Explanation: Integration requires configuration steps to ensure that alerts from Microsoft 365 Defender and Azure Defender properly flow into Microsoft Sentinel.
Single Select: What type of rule in Microsoft Sentinel can be used to detect potential threats by looking for anomalies without prior knowledge of attack patterns?
- A) Scheduled query rules
- B) Microsoft security rules
- C) Fusion rules
- D) ML behavior analytics
Answer: D. ML behavior analytics
Explanation: ML behavior analytics rules leverage machine learning to detect anomalies and potential threats without relying on known attack patterns, unlike scheduled queries or fusion rules which typically require predefined patterns.
True or False: Custom alerts in Microsoft Sentinel can be configured to automatically resolve themselves.
- Answer: True
Explanation: Custom alerts can be set up with automated response actions that include the capability to resolve alerts based on certain conditions or after a certain action has been taken.
Multiple Select: What information must be specified when creating a custom detection rule in Microsoft Sentinel? (Select all that apply)
- A) Query frequency
- B) Query period
- C) Rule name
- D) Data retention policy
Answer: A, B, C
Explanation: A custom detection rule requires specific information such as how often the query runs (Query frequency), over which period of collected data (Query period), and a name for the rule (Rule name). Data retention policy is a separate configuration that does not need to be defined for each rule.
True or False: The same custom detection rule in Microsoft Sentinel can’t target multiple data sources.
- Answer: False
Explanation: A custom detection rule in Microsoft Sentinel can be configured to query across multiple data sources as long as they are available within Sentinel’s workspace.
Single Select: What is the role of a playbook in Microsoft Sentinel?
- A) To provide detailed analytics of past incidents
- B) To define automated responses to alerts
- C) To create visualizations of security data
- D) To manage user access to the Sentinel workspace
Answer: B. To define automated responses to alerts
Explanation: Playbooks in Microsoft Sentinel are used to define and manage automated responses to alerts, often by using Azure Logic Apps.
True or False: When creating custom alerts in Microsoft Sentinel, you are limited to using only built-in actions and cannot use actions from Logic Apps.
- Answer: False
Explanation: Microsoft Sentinel playbooks are based on Azure Logic Apps, which allows for using both built-in actions and custom actions defined within Logic Apps.
Multiple Select: Which of the following are potential trigger actions for a custom alert in Microsoft Sentinel? (Select all that apply)
- A) Creating an incident
- B) Sending an email notification
- C) Automatically mitigating a threat
- D) Publishing a tweet
Answer: A, B, C
Explanation: When a custom alert fires, you can configure it to create an incident, send an email notification, or execute automated threat mitigation steps. Publishing a tweet is not a standard action for security alerts.
True or False: It is possible to enable and disable custom alert rules in Microsoft Sentinel based on a schedule.
- Answer: True
Explanation: In Microsoft Sentinel, you can enable or disable custom alert rules manually or by setting up a schedule using Azure Logic Apps or automation rules.
Interview Questions
What are custom detections in Microsoft Defender?
Custom detections are rules that you create to detect specific threats or activities in your environment.
How can you create custom detections in Microsoft Defender?
You can create custom detections in the Microsoft Defender Security Center portal using the custom detection feature.
What are some examples of custom detections you can create in Microsoft Defender?
Examples of custom detections you can create in Microsoft Defender include detecting malicious PowerShell scripts, detecting lateral movement, and detecting specific file or registry changes.
How do you manage custom detections in Microsoft Defender?
You can manage custom detections in the Microsoft Defender Security Center portal by viewing and editing existing detections, creating new detections, and enabling or disabling detections.
What are the benefits of using custom detections in Microsoft Defender?
Custom detections can help you better detect and respond to specific threats in your environment, improving the security of your organization.
What is the difference between custom detections and built-in detections in Microsoft Defender?
Built-in detections are pre-configured detections provided by Microsoft, while custom detections are rules you create yourself to detect specific threats or activities.
How can you configure alerts for custom detections in Microsoft Defender?
You can configure alerts for custom detections in the Microsoft Defender Security Center portal by enabling the “Generate alerts for this detection” option when creating or editing a detection.
How do you manage alerts in Microsoft Defender?
You can manage alerts in the Microsoft Defender Security Center portal by viewing and responding to alerts, marking alerts as false positives, and configuring alert settings.
What are the different alert severities in Microsoft Defender?
The different alert severities in Microsoft Defender are high, medium, and low.
How can you filter alerts in Microsoft Defender by severity?
You can filter alerts in Microsoft Defender by severity using the Severity drop-down menu on the Alerts page in the Microsoft Defender Security Center portal.
How can you configure email notifications for alerts in Microsoft Defender?
You can configure email notifications for alerts in Microsoft Defender by configuring the “Email Notification Settings” in the Microsoft Defender Security Center portal.
How do you create custom alert templates in Microsoft Defender?
You can create custom alert templates in Microsoft Defender by creating a JSON file with the desired template and uploading it to the Microsoft Defender Security Center portal.
How can you use Power BI to analyze alert data in Microsoft Defender?
You can use Power BI to analyze alert data in Microsoft Defender by connecting to the Microsoft Defender API and creating custom visualizations and dashboards.
How can you use the Microsoft Graph API to manage alerts in Microsoft Defender?
You can use the Microsoft Graph API to manage alerts in Microsoft Defender by creating and modifying alerts programmatically.
What are some best practices for managing custom detections and alerts in Microsoft Defender?
Some best practices for managing custom detections and alerts in Microsoft Defender include regularly reviewing and updating detections, collaborating with other security teams, and continuously monitoring and tuning your alerting strategy.
This blog on configuring and managing custom detections and alerts for SC-200 was super helpful!
Can anyone explain how to create alerts for specific IP addresses?
I appreciate the detailed steps on creating custom detections. They are very easy to follow.
How do I test my custom alerts before deploying them?
I found this blog post very informative. Thanks!
Some parts of the setup were a bit hard to follow. A video would have been better.
Do custom detections consume more resources compared to standard ones?
Does anyone have tips on optimizing rule performance in Microsoft Sentinel?