Microsoft Entra ID Hybrid Health AD FS Service Delete

AzureActivity
| where CategoryValue =~ 'Administrative'
| where ResourceProviderValue =~ 'Microsoft.ADHybridHealthService'
| where _ResourceId has 'AdFederationService'
| where OperationNameValue =~ 'Microsoft.ADHybridHealthService/services/delete'
| extend claimsJson = parse_json(Claims)
| extend AppId = tostring(claimsJson.appid), AccountName = tostring(claimsJson.name), Name = tostring(split(Caller,'@',0)[0]), UPNSuffix = tostring(split(Caller,'@',1)[0])
| project-away claimsJson

triggerOperator: gt
queryFrequency: 1d
description: |
  'This detection uses AzureActivity logs (Administrative category) to identify the deletion of an Microsoft Entra ID 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 no longer needed via HTTP requests to Azure.
  More information is available in this blog https://o365blog.com/post/hybridhealthagent/'  
status: Available
kind: Scheduled
triggerThreshold: 0
requiredDataConnectors:
- connectorId: AzureActivity
  dataTypes:
  - AzureActivity
version: 2.0.3
queryPeriod: 1d
name: Microsoft Entra ID Hybrid Health AD FS Service Delete
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/AADHybridHealthADFSServiceDelete.yaml
id: 86a036b2-3686-42eb-b417-909fc0867771
tags:
- SimuLand
tactics:
- DefenseEvasion
relevantTechniques:
- T1578.003
severity: Medium
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: Caller
  - identifier: Name
    columnName: Name
  - identifier: UPNSuffix
    columnName: UPNSuffix
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: CallerIpAddress
  entityType: IP
query: |
  AzureActivity
  | where CategoryValue =~ 'Administrative'
  | where ResourceProviderValue =~ 'Microsoft.ADHybridHealthService'
  | where _ResourceId has 'AdFederationService'
  | where OperationNameValue =~ 'Microsoft.ADHybridHealthService/services/delete'
  | extend claimsJson = parse_json(Claims)
  | extend AppId = tostring(claimsJson.appid), AccountName = tostring(claimsJson.name), Name = tostring(split(Caller,'@',0)[0]), UPNSuffix = tostring(split(Caller,'@',1)[0])
  | project-away claimsJson  

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2023-02-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/86a036b2-3686-42eb-b417-909fc0867771')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/86a036b2-3686-42eb-b417-909fc0867771')]",
      "properties": {
        "alertRuleTemplateName": "86a036b2-3686-42eb-b417-909fc0867771",
        "customDetails": null,
        "description": "'This detection uses AzureActivity logs (Administrative category) to identify the deletion of an Microsoft Entra ID Hybrid Health AD FS service instance in a tenant.\nA threat actor can create a new AD Health ADFS service and create a fake server to spoof AD FS signing logs.\nThe health AD FS service can then be deleted after it is no longer needed via HTTP requests to Azure.\nMore information is available in this blog https://o365blog.com/post/hybridhealthagent/'\n",
        "displayName": "Microsoft Entra ID Hybrid Health AD FS Service Delete",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "Caller",
                "identifier": "FullName"
              },
              {
                "columnName": "Name",
                "identifier": "Name"
              },
              {
                "columnName": "UPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "CallerIpAddress",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/AADHybridHealthADFSServiceDelete.yaml",
        "query": "AzureActivity\n| where CategoryValue =~ 'Administrative'\n| where ResourceProviderValue =~ 'Microsoft.ADHybridHealthService'\n| where _ResourceId has 'AdFederationService'\n| where OperationNameValue =~ 'Microsoft.ADHybridHealthService/services/delete'\n| extend claimsJson = parse_json(Claims)\n| extend AppId = tostring(claimsJson.appid), AccountName = tostring(claimsJson.name), Name = tostring(split(Caller,'@',0)[0]), UPNSuffix = tostring(split(Caller,'@',1)[0])\n| project-away claimsJson\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Medium",
        "status": "Available",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "tags": [
          "SimuLand"
        ],
        "techniques": [
          "T1578"
        ],
        "templateVersion": "2.0.3",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}