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

status: Available
requiredDataConnectors:
- connectorId: AzureActivity
  dataTypes:
  - AzureActivity
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/'
version: 2.0.3
name: Microsoft Entra ID Hybrid Health AD FS Service Delete
kind: Scheduled
queryPeriod: 1d
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure%20Activity/Analytic%20Rules/AADHybridHealthADFSServiceDelete.yaml
tags:
- SimuLand
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: FullName
    columnName: Caller
  - identifier: Name
    columnName: Name
  - identifier: UPNSuffix
    columnName: UPNSuffix
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: CallerIpAddress
relevantTechniques:
- T1578.003
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
id: 86a036b2-3686-42eb-b417-909fc0867771
triggerOperator: gt
queryFrequency: 1d
tactics:
- DefenseEvasion
severity: Medium
triggerThreshold: 0

{
  "$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%20Activity/Analytic%20Rules/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"
    }
  ]
}