Investigate security alerts from Defender for Identity
5 minutes
5 Questions
Microsoft Defender for Identity is a cloud-based security solution that leverages on-premises Active Directory signals to identify, detect, and investigate advanced threats, compromised identities, and malicious insider actions. As a Security Operations Analyst, investigating security alerts from D…Microsoft Defender for Identity is a cloud-based security solution that leverages on-premises Active Directory signals to identify, detect, and investigate advanced threats, compromised identities, and malicious insider actions. As a Security Operations Analyst, investigating security alerts from Defender for Identity is crucial for protecting organizational resources.
When investigating alerts, analysts should first access the Microsoft 365 Defender portal where Defender for Identity alerts are consolidated. Each alert contains essential information including the alert title, severity level, affected entities, timeline of events, and evidence collected during detection.
The investigation process begins by reviewing the alert details page, which provides context about the suspicious activity. Analysts should examine the affected user accounts, source computers, and target resources involved in the potential threat. The timeline view shows the sequence of events, helping analysts understand the attack progression.
Key alert categories include reconnaissance activities (such as account enumeration and network mapping), compromised credential attacks (like brute force attempts and pass-the-hash attacks), lateral movement detection, and domain dominance activities. Each category requires specific investigation approaches.
Analysts should correlate Defender for Identity alerts with other security signals from Microsoft Defender for Endpoint, Microsoft Defender for Cloud Apps, and Azure Active Directory Identity Protection. This correlation provides a comprehensive view of potential attack chains.
During investigation, analysts can use the entity profile pages to view historical behavior patterns and determine if activities are anomalous. The learning period data helps distinguish between normal user behavior and genuinely suspicious actions.
After completing the investigation, analysts should classify the alert appropriately as true positive, benign true positive, or false positive. For confirmed threats, immediate remediation actions include resetting compromised passwords, disabling affected accounts, and isolating compromised devices. Documenting findings and updating detection rules based on investigation outcomes improves future security posture.
Investigate Security Alerts from Defender for Identity
Why It Is Important
Microsoft Defender for Identity is a cloud-based security solution that leverages your on-premises Active Directory signals to identify, detect, and investigate advanced threats, compromised identities, and malicious insider actions. Understanding how to investigate security alerts from this tool is essential for Security Operations Analysts because identity-based attacks are among the most common and damaging attack vectors in modern enterprises. Proper investigation skills enable rapid threat containment and minimize organizational risk.
What It Is
Defender for Identity monitors user activities and information across your network, including permissions and group membership, creating a behavioral baseline for each user. It then detects anomalies using adaptive built-in intelligence, providing insights into suspicious activities and events. Security alerts are generated when potentially malicious activities are detected, such as:
The investigation process follows these key steps:
1. Alert Triage: Access alerts through the Microsoft 365 Defender portal. Each alert displays severity level, status, category, and detection source.
2. Alert Details Review: Click on an alert to view detailed information including the affected entities (users, computers, resources), timeline of events, and evidence collected.
3. Entity Investigation: Use the entity page to examine the user or device profile, view the timeline of activities, and identify related alerts. The lateral movement paths feature shows potential attack paths.
4. Evidence Analysis: Review raw data, network activities, and authentication events associated with the alert.
5. Remediation Actions: Based on findings, take actions such as disabling accounts, resetting passwords, or isolating machines.
Key Investigation Features
- Attack Timeline: Visual representation of attack progression - Lateral Movement Paths: Shows how attackers could move through the network - Entity Profiles: Comprehensive view of user and device activities - Integration with Microsoft 365 Defender: Correlates alerts across endpoints, email, and identity
Exam Tips: Answering Questions on Investigate Security Alerts from Defender for Identity
Focus on these key areas:
1. Know the alert categories: Memorize the main categories - Reconnaissance, Compromised Credentials, Lateral Movement, Domain Dominance, and Exfiltration.
2. Understand alert severity levels: High, Medium, and Low severity determine investigation priority. High severity alerts indicate confirmed malicious activity.
3. Remember the portal location: Defender for Identity alerts are accessed through the Microsoft 365 Defender portal (security.microsoft.com), not a separate console.
4. Lateral Movement Paths: Questions often test knowledge of this feature. Know that it identifies potential paths attackers could use to reach sensitive accounts.
5. Entity pages are central: When asked about investigating a specific user or computer, the entity page provides consolidated information.
6. Remediation options: Know available response actions like disabling accounts in Active Directory, requiring password reset, and adding users to watchlists.
7. Sensor requirements: Remember that Defender for Identity requires sensors installed on domain controllers or as standalone sensors.
8. Honeytoken accounts: Understand that these are decoy accounts used to detect reconnaissance and credential theft attempts.
9. Practice scenario-based questions: Exam questions often present a scenario and ask which investigation step or feature to use. Focus on matching symptoms to alert types.
10. Integration knowledge: Understand how Defender for Identity integrates with other Microsoft 365 Defender components for unified investigation experiences.