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Azure Active Directory Hybrid Health AD FS Service Delete

This detection uses azureactivity logs (Administrative category) to identify the deletion of an Azure AD Hybrid health AD FS service instance in a tenant. A threat actor can create a new AD Health ADFS service and create a fake server to spoof AD FS signing logs. The health AD FS service can then be deleted after it is not longer needed via HTTP requests to Azure.

MITRE ATT&CK

T1578.003

defense-evasion

Detection Query

selection:
  CategoryValue: Administrative
  ResourceProviderValue: Microsoft.ADHybridHealthService
  ResourceId|contains: AdFederationService
  OperationNameValue: Microsoft.ADHybridHealthService/services/delete
condition: selection

Author

Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research), MSTIC

Created

2021-08-26

Data Sources

azureactivitylogs

Platforms

azure

References

https://o365blog.com/post/hybridhealthagent/

Tags

attack.defense-evasionattack.t1578.003

Raw Content

title: Azure Active Directory Hybrid Health AD FS Service Delete
id: 48739819-8230-4ee3-a8ea-e0289d1fb0ff
status: test
description: |
    This detection uses azureactivity logs (Administrative category) to identify the deletion of an Azure AD Hybrid health AD FS service instance in a tenant.
    A threat actor can create a new AD Health ADFS service and create a fake server to spoof AD FS signing logs.
    The health AD FS service can then be deleted after it is not longer needed via HTTP requests to Azure.
references:
    - https://o365blog.com/post/hybridhealthagent/
author: Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research), MSTIC
date: 2021-08-26
modified: 2023-10-11
tags:
    - attack.defense-evasion
    - attack.t1578.003
logsource:
    product: azure
    service: activitylogs
detection:
    selection:
        CategoryValue: 'Administrative'
        ResourceProviderValue: 'Microsoft.ADHybridHealthService'
        ResourceId|contains: 'AdFederationService'
        OperationNameValue: 'Microsoft.ADHybridHealthService/services/delete'
    condition: selection
falsepositives:
    - Legitimate AAD Health AD FS service instances being deleted in a tenant
level: medium