Hunting the Threats Using a Broader XDR with Defender for Endpoint
#DefenderforEndpoint
Introduction
As cyber threats continue to evolve, security teams need more comprehensive detection, investigation, and response capabilities. Extended Detection and Response (XDR) solutions offer a proactive approach by correlating telemetry from various sources to detect sophisticated threats. Microsoft Defender for Endpoint (MDE) is a powerful XDR solution that enables security professionals to hunt threats across endpoints and beyond.
In this blog, we’ll explore how a broader XDR strategy using Defender for Endpoint enhances threat hunting capabilities, provides better visibility, and enables faster remediation.
What is a Broader XDR?
XDR is an evolution of Endpoint Detection and Response (EDR) that extends security coverage beyond just endpoints. A broader XDR solution integrates multiple security signals across an organization’s ecosystem, including:
Endpoints (Defender for Endpoint, Windows, Linux, macOS, iOS, Android)
Email & Collaboration (Defender for Office 365, Exchange, SharePoint, Teams)
Identity & Access (Defender for Identity, Microsoft Entra ID – formerly Azure AD)
Cloud Apps & Workloads (Defender for Cloud, Microsoft Sentinel, Azure Security Center)
Network Traffic (Network protection, Microsoft Defender Threat Intelligence)
By aggregating and correlating security telemetry from various sources, a broader XDR allows security teams to:
Detect threats faster and with higher fidelity.
Investigate incidents with a comprehensive view of the attack path.
Automate responses to reduce dwell time and impact.
Threat Hunting with Defender for Endpoint in a Broader XDR
Defender for Endpoint plays a crucial role in hunting threats across a broader XDR environment. It provides detailed telemetry from endpoint activities and integrates with other Microsoft security solutions to offer cross-domain threat detection and response.
1. Leveraging Advanced Hunting Queries
Defender for Endpoint offers an advanced hunting capability using Kusto Query Language (KQL). This enables security analysts to proactively search for indicators of compromise (IoCs) or abnormal behavior across endpoints.
Example KQL Query: Detecting Suspicious PowerShell Activity
DeviceProcessEvents
| where ProcessCommandLine contains "Invoke-WebRequest"
or ProcessCommandLine contains "DownloadString"
| project Timestamp, DeviceName, InitiatingProcessFileName, ProcessCommandLine
This query helps identify PowerShell scripts attempting to download remote payloads, which is a common initial access technique.
2. Cross-Domain Investigation with Microsoft 365 Defender
With Microsoft 365 Defender, security teams can correlate endpoint events with signals from:
Defender for Identity (compromised accounts and lateral movement detection)
Defender for Office 365 (email-based phishing attacks)
Defender for Cloud Apps (malicious app activities)
For example, an attack that starts with a phishing email (Defender for Office 365) can be traced to endpoint exploitation (Defender for Endpoint) and lateral movement using stolen credentials (Defender for Identity). This level of integration provides unparalleled visibility into modern cyber threats.
3. Automating Threat Response with XDR
Automation is key to reducing mean time to detect (MTTD) and mean time to respond (MTTR). Defender for Endpoint integrates with Microsoft Sentinel and Defender XDR to:
Automatically isolate compromised devices.
Revoke stolen user credentials.
Block malicious IPs and domains across the organization.
Trigger remediation playbooks in Sentinel.
Example: Automated Containment Playbook in Sentinel
A detected ransomware attack can automatically trigger a playbook in Microsoft Sentinel that:
Identifies the compromised device using Defender for Endpoint telemetry.
Isolates the device to prevent further spread.
Notifies the SOC team and creates an incident.
Blocks associated indicators (IP, domain, hash) across the network.
4. Integrating Threat Intelligence for Proactive Hunting
Defender for Endpoint is enhanced by Microsoft Defender Threat Intelligence (MDTI), which provides real-time threat intelligence feeds. Analysts can:
Enrich hunting queries with up-to-date IoCs.
Detect threats targeting specific industries.
Proactively block emerging threats before exploitation.
Threat Intelligence Query: Correlating Threat Feeds with Device Events
let threat_indicators = ThreatIntelligenceIndicator
| where Action == "Alert";
DeviceNetworkEvents
| where RemoteIP in (threat_indicators)
| project Timestamp, DeviceName, RemoteIP, RemoteUrl
This query identifies endpoint connections to malicious IPs based on real-time threat intelligence.
Real-World Threat Hunting Scenario
Let’s walk through a real-world use case where a broader XDR approach with Defender for Endpoint helps detect and mitigate an advanced attack.
Scenario: Ransomware Attack via Phishing Email
Step 1: Phishing Detection in Defender for Office 365
An employee receives a phishing email with a malicious attachment.
Defender for Office 365 detects the malicious email and triggers an alert.
Step 2: Endpoint Compromise Detected by Defender for Endpoint
The employee downloads and executes the attachment.
Defender for Endpoint detects suspicious process execution (e.g., PowerShell spawning encoded commands).
An alert is generated in Microsoft 365 Defender.
Step 3: Identity Compromise Tracked by Defender for Identity
The attacker steals credentials and attempts lateral movement.
Defender for Identity detects anomalous login attempts and unusual account behavior.
The compromised account is automatically disabled.
Step 4: Incident Investigation & Response in Microsoft Sentinel
Sentinel aggregates alerts from Defender for Endpoint, Defender for Identity, and Defender for Office 365.
SOC analysts investigate the full attack timeline.
A remediation playbook is triggered to:
Isolate the affected endpoint.
Reset the compromised credentials.
Block the malicious domain across the organization.
By leveraging a broader XDR strategy, security teams were able to detect, correlate, and respond to the attack efficiently, minimizing damage and preventing data exfiltration.
Conclusion
A broader XDR approach with Defender for Endpoint provides unparalleled visibility and response capabilities against modern cyber threats. By integrating endpoint, identity, cloud, and network signals, security teams can:
Improve detection accuracy through correlated insights.
Proactively hunt for threats using KQL queries and threat intelligence.
Automate incident response to contain threats rapidly.
As cyber threats continue to evolve, organizations must embrace XDR solutions like Microsoft Defender to stay ahead of attackers and strengthen their security posture.
Next Steps
Start Hunting: Explore the advanced hunting capabilities in Microsoft Defender for Endpoint.
Integrate XDR: Enable cross-domain telemetry with Microsoft 365 Defender and Sentinel.
Automate Response: Set up automated playbooks to reduce response time.
Stay Informed: Keep up with emerging threats using Defender Threat Intelligence.
By leveraging a broader XDR approach, security teams can proactively hunt, detect, and respond to threats with greater speed and efficiency.