Microsoft 365 Defender simplifies and expands Microsoft security capabilities by consolidating data and functionality into unifiedexperiences in the Microsoft 365 security center.
With advanced hunting, customers can continue using the powerful Kusto-based query interface to hunt across a device-optimized schema for Microsoft Defender for Endpoint. You can also switch to the Microsoft 365 security center, where we’ve surfaced additional email, identity, and app data consolidated under Microsoft 365 Defender.
Customers who actively use advanced hunting in Microsoft Defender for Endpoint are advised to note the following details to ensure a smooth transition to advanced hunting in Microsoft 365 Defender:
You can now edit your Microsoft Defender for Endpoint custom detection rules in Microsoft 365 Defender. At the same time, alerts generated by custom detection rules in Microsoft 365 Defender will now be displayed in a newly built alert page that provides the following information:
Alert title and description
Actions taken in response to the alert
Query results that triggered the alert (timeline and table views)
Read through the following sections for tips on how you can transition your Microsoft Defender for Endpoint rules smoothly to Microsoft 365 Defender.
Migrate custom detection rules
When Microsoft Defender for Endpoint rules are edited in Microsoft 365 Defender, they can continue to function as before if the resulting query looks at device tables only. For example, alerts generated by custom detection rules that query only device tables will continue to be delivered to your SIEM and generate email notifications, depending on how you’ve configured these in Microsoft Defender for Endpoint. Any existing suppression rules in Microsoft Defender for Endpoint will also continue to apply.
Once you edit a Microsoft Defender for Endpoint rule so that it queries identity and emailtables, which are only available in Microsoft 365 Defender, the rule is automatically moved to Microsoft 365 Defender. Alerts generated by the migrated rule:
Are no longer visible in the Microsoft Defender Security Center
Will cease being delivered to your SIEM or generate email notifications. To work around these changes, configure notifications through Microsoft 365 Defender to get the alerts. You can use the Microsoft 365 Defender API to receive notifications for custom detection alerts or related incidents.
Won't be suppressed by Microsoft Defender for Endpoint suppression rules. To prevent alerts from being generated for certain users, devices, or mailboxes, modify the corresponding queries to exclude those entities explicitly.
If you do edit a rule this way, you will be prompted for confirmation before such changes are applied.
Write queries without DeviceAlertEvents
In the Microsoft 365 Defender, the AlertInfoand AlertEvidencetables are provided to accommodate the diverse set of information that accompany alerts from various sources. Once you transition to advanced hunting in Microsoft 365 Defender, you’ll need to make adjustments so your queries get the same alert information that you used to get from the DeviceAlertEvents table in the Microsoft Defender for Endpoint schema.
In general, you can get all the device-specific Microsoft Defender for Endpoint alert info by filtering the AlertInfo table by ServiceSource and then joining each unique ID with the AlertEvidence table, which provides detailed event and entity information. See the sample query below:
AlertInfo | where Timestamp > ago(7d) | where ServiceSource== "Microsoft Defender for Endpoint" | join AlertEvidence on AlertId
This query will yield many more columns than simply taking records from DeviceAlertEvents. To keep results manageable, use project to get only the columns you are interested in. The query below projects columns you might be interested in when investigating detected PowerShell activity:
AlertInfo | where Timestamp > ago(7d) | where ServiceSource== "Microsoft Defender for Endpoint" and AttackTechniques has "powershell" | join AlertEvidence on AlertId | project Timestamp, Title, AlertId, DeviceName, FileName, ProcessCommandLine
Important note on the visibility of data in Microsoft Defender for Endpoint
Saved queries and custom detection rules that use tables that are not in Microsoft Defender for Endpoint are visible in Microsoft 365 security center(security.microsoft.com) only—you will not see them in the Microsoft Defender Security Center. In the Microsoft Defender Security Center, you will see only the queries and rules that are based on the tables available in this portal.
Let us know how we can help
While the move to Microsoft 365 Defender offers limitless benefits especially to customers who have deployed multiple Microsoft 365 security solutions, we understand how change can always present challenges. We’d like to encourage all customers to send us feedback about their experiences managing this change and suggestions on how we can help further. Send us feedback through the portals or contact us at firstname.lastname@example.org.