Cross-tenant Access Settings Organization Inbound Direct Settings Changed

//In User & Groups and in Applications, the following "AccessType" values in columns PremodifiedInboundSettings and ModifiedInboundSettings are interpreted accordingly:
// When Access Type in premodified inbound settings value was 1 that means that the initial access was allowed. When Access Type in premodified inbound settings value was 2 that means that the initial access was blocked. 
// When Access Type in modified inbound settings value is 1 that means that now access is allowed. When Access Type in modified inbound settings value is 2 that means that now access is blocked. 
AuditLogs
| where OperationName has "Update a partner cross-tenant access setting"
| mv-apply TargetResource = TargetResources on
  (
      where TargetResource.type =~ "Policy"
      | extend Properties = TargetResource.modifiedProperties
  )
| mv-apply Property = Properties on
  (
      where Property.displayName =~ "b2bDirectConnectInbound"
      | extend PremodifiedInboundSettings = trim('"',tostring(Property.oldValue)),
               ModifiedInboundSettings = trim(@'"',tostring(Property.newValue))
  )
| extend InitiatedByActionUserInformation = iff(isnotempty(InitiatedBy.user.userPrincipalName), InitiatedBy.user.userPrincipalName, InitiatedBy.app.displayName)
| extend InitiatedByIPAdress = InitiatedBy.user.ipAddress
| where PremodifiedInboundSettings != ModifiedInboundSettings
| extend Name = tostring(split(InitiatedByActionUserInformation,'@',0)[0]), UPNSuffix = tostring(split(InitiatedByActionUserInformation,'@',1)[0])

kind: Scheduled
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Active Directory/Analytic Rules/Cross-tenantAccessSettingsOrganizationInboundDirectSettingsChanged.yaml
severity: Medium
name: Cross-tenant Access Settings Organization Inbound Direct Settings Changed
entityMappings:
- entityType: Account
  fieldMappings:
  - columnName: Name
    identifier: Name
  - columnName: UPNSuffix
    identifier: UPNSuffix
- entityType: IP
  fieldMappings:
  - columnName: InitiatedByIPAdress
    identifier: Address
relevantTechniques:
- T1078.004
- T1136.003
- T1087.004
queryFrequency: 2d
triggerThreshold: 0
queryPeriod: 2d
description: |
    'Organizations are added in the Cross-tenant Access Settings to control communication inbound or outbound for users and applications. This detection notifies when Organization Inbound Direct Settings are changed for "Users & Groups" and for "Applications".'
id: 276d5190-38de-4eb2-9933-b3b72f4a5737
version: 1.0.1
tactics:
- InitialAccess
- Persistence
- Discovery
query: |
  //In User & Groups and in Applications, the following "AccessType" values in columns PremodifiedInboundSettings and ModifiedInboundSettings are interpreted accordingly:
  // When Access Type in premodified inbound settings value was 1 that means that the initial access was allowed. When Access Type in premodified inbound settings value was 2 that means that the initial access was blocked. 
  // When Access Type in modified inbound settings value is 1 that means that now access is allowed. When Access Type in modified inbound settings value is 2 that means that now access is blocked. 
  AuditLogs
  | where OperationName has "Update a partner cross-tenant access setting"
  | mv-apply TargetResource = TargetResources on
    (
        where TargetResource.type =~ "Policy"
        | extend Properties = TargetResource.modifiedProperties
    )
  | mv-apply Property = Properties on
    (
        where Property.displayName =~ "b2bDirectConnectInbound"
        | extend PremodifiedInboundSettings = trim('"',tostring(Property.oldValue)),
                 ModifiedInboundSettings = trim(@'"',tostring(Property.newValue))
    )
  | extend InitiatedByActionUserInformation = iff(isnotempty(InitiatedBy.user.userPrincipalName), InitiatedBy.user.userPrincipalName, InitiatedBy.app.displayName)
  | extend InitiatedByIPAdress = InitiatedBy.user.ipAddress
  | where PremodifiedInboundSettings != ModifiedInboundSettings
  | extend Name = tostring(split(InitiatedByActionUserInformation,'@',0)[0]), UPNSuffix = tostring(split(InitiatedByActionUserInformation,'@',1)[0])  
status: Available
requiredDataConnectors:
- dataTypes:
  - AuditLogs
  connectorId: AzureActiveDirectory
triggerOperator: gt

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/276d5190-38de-4eb2-9933-b3b72f4a5737')]",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/276d5190-38de-4eb2-9933-b3b72f4a5737')]",
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules",
      "kind": "Scheduled",
      "apiVersion": "2022-11-01-preview",
      "properties": {
        "displayName": "Cross-tenant Access Settings Organization Inbound Direct Settings Changed",
        "description": "'Organizations are added in the Cross-tenant Access Settings to control communication inbound or outbound for users and applications. This detection notifies when Organization Inbound Direct Settings are changed for \"Users & Groups\" and for \"Applications\".'\n",
        "severity": "Medium",
        "enabled": true,
        "query": "//In User & Groups and in Applications, the following \"AccessType\" values in columns PremodifiedInboundSettings and ModifiedInboundSettings are interpreted accordingly:\n// When Access Type in premodified inbound settings value was 1 that means that the initial access was allowed. When Access Type in premodified inbound settings value was 2 that means that the initial access was blocked. \n// When Access Type in modified inbound settings value is 1 that means that now access is allowed. When Access Type in modified inbound settings value is 2 that means that now access is blocked. \nAuditLogs\n| where OperationName has \"Update a partner cross-tenant access setting\"\n| mv-apply TargetResource = TargetResources on\n  (\n      where TargetResource.type =~ \"Policy\"\n      | extend Properties = TargetResource.modifiedProperties\n  )\n| mv-apply Property = Properties on\n  (\n      where Property.displayName =~ \"b2bDirectConnectInbound\"\n      | extend PremodifiedInboundSettings = trim('\"',tostring(Property.oldValue)),\n               ModifiedInboundSettings = trim(@'\"',tostring(Property.newValue))\n  )\n| extend InitiatedByActionUserInformation = iff(isnotempty(InitiatedBy.user.userPrincipalName), InitiatedBy.user.userPrincipalName, InitiatedBy.app.displayName)\n| extend InitiatedByIPAdress = InitiatedBy.user.ipAddress\n| where PremodifiedInboundSettings != ModifiedInboundSettings\n| extend Name = tostring(split(InitiatedByActionUserInformation,'@',0)[0]), UPNSuffix = tostring(split(InitiatedByActionUserInformation,'@',1)[0])\n",
        "queryFrequency": "P2D",
        "queryPeriod": "P2D",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0,
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "InitialAccess",
          "Persistence",
          "Discovery"
        ],
        "techniques": [
          "T1078.004",
          "T1136.003",
          "T1087.004"
        ],
        "alertRuleTemplateName": "276d5190-38de-4eb2-9933-b3b72f4a5737",
        "customDetails": null,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "identifier": "Name",
                "columnName": "Name"
              },
              {
                "identifier": "UPNSuffix",
                "columnName": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "identifier": "Address",
                "columnName": "InitiatedByIPAdress"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Active Directory/Analytic Rules/Cross-tenantAccessSettingsOrganizationInboundDirectSettingsChanged.yaml",
        "status": "Available",
        "templateVersion": "1.0.1"
      }
    }
  ]
}