Digital Guardian - Exfiltration to external domain

let corp_domain = dynamic(['example.com']);     //add all corporate domains to this list
DigitalGuardianDLPEvent
| where NetworkApplicationProtocol =~ 'SMTP'
| where isnotempty(inspected_document)
| extend s_domain = extract(@'@(.*)', 1, SrcUserName)
| extend d_domain = extract(@'@(.*)', 1, DstUserName)
| where s_domain in~ (corp_domain)
| where d_domain !in (corp_domain)
| extend AccountCustomEntity = SrcUserName

description: |
    'Detects exfiltration to external domain.'
kind: Scheduled
query: |
  let corp_domain = dynamic(['example.com']);     //add all corporate domains to this list
  DigitalGuardianDLPEvent
  | where NetworkApplicationProtocol =~ 'SMTP'
  | where isnotempty(inspected_document)
  | extend s_domain = extract(@'@(.*)', 1, SrcUserName)
  | extend d_domain = extract(@'@(.*)', 1, DstUserName)
  | where s_domain in~ (corp_domain)
  | where d_domain !in (corp_domain)
  | extend AccountCustomEntity = SrcUserName  
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: AccountCustomEntity
  entityType: Account
status: Available
tactics:
- Exfiltration
queryFrequency: 1h
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/DigitalGuardianDLP/Analytic Rules/DigitalGuardianFileSentToExternalDomain.yaml
name: Digital Guardian - Exfiltration to external domain
version: 1.0.0
triggerOperator: gt
requiredDataConnectors:
- dataTypes:
  - DigitalGuardianDLPEvent
  connectorId: DigitalGuardianDLP
severity: Medium
queryPeriod: 1h
id: a19885c8-1e44-47e3-81df-d1d109f5c92d
relevantTechniques:
- T1048
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": "2023-02-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/a19885c8-1e44-47e3-81df-d1d109f5c92d')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/a19885c8-1e44-47e3-81df-d1d109f5c92d')]",
      "properties": {
        "alertRuleTemplateName": "a19885c8-1e44-47e3-81df-d1d109f5c92d",
        "customDetails": null,
        "description": "'Detects exfiltration to external domain.'\n",
        "displayName": "Digital Guardian - Exfiltration to external domain",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "AccountCustomEntity",
                "identifier": "Name"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/DigitalGuardianDLP/Analytic Rules/DigitalGuardianFileSentToExternalDomain.yaml",
        "query": "let corp_domain = dynamic(['example.com']);     //add all corporate domains to this list\nDigitalGuardianDLPEvent\n| where NetworkApplicationProtocol =~ 'SMTP'\n| where isnotempty(inspected_document)\n| extend s_domain = extract(@'@(.*)', 1, SrcUserName)\n| extend d_domain = extract(@'@(.*)', 1, DstUserName)\n| where s_domain in~ (corp_domain)\n| where d_domain !in (corp_domain)\n| extend AccountCustomEntity = SrcUserName\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Exfiltration"
        ],
        "techniques": [
          "T1048"
        ],
        "templateVersion": "1.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}