Microsoft Defender XDR (Extended Detection and Response) unifies signals from Defender for Endpoint, Office 365, Identity, and Cloud Apps into a single correlated incident view. Here's what it means for MSP clients.
Key takeaways
- 1Endpoint signals — from Defender for Business on enrolled devices (malware detections, suspicious process activity, lateral movement)
- 2Email signals — from Defender for Office 365 (phishing links clicked, malicious attachments opened)
- 3Identity signals — from Entra ID Identity Protection (sign-in risk detections, risky users)
- 4Cloud app signals — from Microsoft Defender for Cloud Apps (where licenced)
Extended Detection and Response (XDR) is the evolution of endpoint security — instead of separate alerts from separate products, XDR correlates signals across the entire attack surface into a unified incident view. Microsoft Defender XDR brings this capability to Business Premium clients by correlating signals across Defender for Business, Defender for Office 365, and Entra ID Identity Protection.
What Defender XDR correlates
- Endpoint signals — from Defender for Business on enrolled devices (malware detections, suspicious process activity, lateral movement)
- Email signals — from Defender for Office 365 (phishing links clicked, malicious attachments opened)
- Identity signals — from Entra ID Identity Protection (sign-in risk detections, risky users)
- Cloud app signals — from Microsoft Defender for Cloud Apps (where licenced)
The correlation advantage
Without XDR, an attacker who clicks a phishing link, receives a credential-stealing payload, and uses those credentials from a foreign country generates three separate alerts in three separate products — none of which individually look critical. Defender XDR correlates these into a single incident: "User X clicked a phishing email → credential theft payload executed → account signed in from unusual location." The attack chain is visible in a single view, and automated response can trigger across all three layers simultaneously.
Automated disruption of attacks
Defender XDR includes automatic attack disruption — Microsoft's AI automatically contains attacks by isolating compromised devices, disabling compromised accounts, and blocking attacker tools before the attack can progress. For ransomware attacks in particular, this can contain a breach to a single device before it spreads to file shares. Optimyze reviews XDR incidents and ensures automated response is configured correctly for every managed client.
