{
  "$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/fe468726-b1dc-4e76-adad-3480de4a2c56')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/fe468726-b1dc-4e76-adad-3480de4a2c56')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "Changes to the Root of the Domain GPO could impact the Tier Model GPOs and other security controls.",
          "alertDisplayNameFormat": "(TM008.1) A Tier 0 GPO was {{ActivityType}} at the Root of the Domain"
        },
        "alertRuleTemplateName": "fe468726-b1dc-4e76-adad-3480de4a2c56",
        "customDetails": {
          "Account": "Account",
          "ActivityType": "ActivityType",
          "AttributeLDAP": "AttributeLDAP",
          "Channel": "Channel",
          "Computer": "Computer",
          "Domain": "Domain",
          "EventData": "EventData",
          "EventID": "EventID",
          "ObjectClass": "ObjectClass",
          "ObjectName": "ObjectName",
          "ObjectTier": "ObjectTier"
        },
        "description": "Linked, Unlinked, or Enforced GPOs at the Root of the Domain which could overwrite Tier Model GPOs.\n",
        "displayName": "PROD (TM008.1) - GPO - Linked, Unlinked, or Enforced at Root of Domain",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "ObjectName",
                "identifier": "FullName"
              }
            ]
          },
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "Computer",
                "identifier": "HostName"
              }
            ]
          },
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "Account",
                "identifier": "FullName"
              }
            ]
          }
        ],
        "eventGroupingSettings": {
          "aggregationKind": "AlertPerResult"
        },
        "incidentConfiguration": {
          "createIncident": true,
          "groupingConfiguration": {
            "enabled": false,
            "lookbackDuration": "PT5H",
            "matchingMethod": "AllEntities",
            "reopenClosedIncident": false
          }
        },
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft%20Active%20Directory%20Tier%20Model/Analytic%20Rules/TM008_GPOLinkedUnlinkedOrEnforcedAtRootOfDomain.yaml",
        "query": "SecurityEvent \n| where EventID == 5136 \n    and EventData matches regex @\"(?i)DC=\"\n    and Activity has \"modified\" \n    and EventData has '\"ObjectClass\">domainDNS'\n    and EventData has '<Data Name=\"AttributeLDAPDisplayName\">gPLink</Data>' \n    and (EventData has ';0]' \n        or EventData has ';1]' \n        or EventData has ';2]')\n    and EventData has '\"OperationType\">%%14674'\n| extend ObjectName = extract(\"<Data Name=\\\"ObjectDN\\\">([^<]+)</Data>\", 1, EventData)\n| where ObjectName startswith \"DC=\" or ObjectName startswith \"dc=\"\n| extend ObjectTier = \"Tier 0\"\n| extend AttributeLDAP = extract(\"<Data Name=\\\"AttributeLDAPDisplayName\\\">([^<]+)</Data>\", 1, EventData)\n| extend AttributeValue = extract(\"\\\\[([^\\\\]]+)\\\\]\", 1, EventData)\n| extend LastThreeChars = substring(AttributeValue, strlen(AttributeValue) - 2, 3)\n| extend AttributeValueDescription = case(\n    LastThreeChars == \";0\", \"Linked\",\n    LastThreeChars == \";1\", \"Unlinked\",\n    LastThreeChars == \";2\", \"Enforced\",\n    \"Unknown\")\n| extend ObjectClass = extract(\"<Data Name=\\\"ObjectClass\\\">([^<]+)</Data>\", 1, EventData)\n| extend Domain = extract(\"([^.]+\\\\.[^.]+)$\", 1, Computer)\n| project TimeGenerated\n   , ObjectName\n   , ObjectTier\n   , ObjectClass\n   , ActivityType = AttributeValueDescription\n   , AttributeLDAP\n   , Account\n   , Domain\n   , Computer\n   , Channel\n   , EventID\n   , EventData\n",
        "queryFrequency": "PT5M",
        "queryPeriod": "PT5M",
        "severity": "High",
        "status": "Available",
        "subTechniques": [
          "T1484.001"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "techniques": [
          "T1484"
        ],
        "templateVersion": "1.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}
