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

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
queryPeriod: 1d
triggerThreshold: 0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/AADHybridHealthADFSServiceDelete.yaml
id: 86a036b2-3686-42eb-b417-909fc0867771
kind: Scheduled
requiredDataConnectors:
- connectorId: AzureActivity
  dataTypes:
  - AzureActivity
tactics:
- DefenseEvasion
severity: Medium
triggerOperator: gt
tags:
- SimuLand
version: 2.0.3
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  
name: Microsoft Entra ID Hybrid Health AD FS Service Delete
queryFrequency: 1d
relevantTechniques:
- T1578.003
entityMappings:
- fieldMappings:
  - columnName: Caller
    identifier: FullName
  - columnName: Name
    identifier: Name
  - columnName: UPNSuffix
    identifier: UPNSuffix
  entityType: Account
- fieldMappings:
  - columnName: CallerIpAddress
    identifier: Address
  entityType: IP

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2024-01-01-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",
        "subTechniques": [
          "T1578.003"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "tags": [
          "SimuLand"
        ],
        "techniques": [
          "T1578"
        ],
        "templateVersion": "2.0.3",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}