TI map Domain entity to DnsEvents

let dt_lookBack = 1h;
let ioc_lookBack = 14d;
let IoCList = externaldata(TimeGenerated:datetime,IoC:string,IoC_Type:string,ExpirationDateTime:datetime,Description:string,Action:string, ConfidenceScore:real, ThreatType:string, Active:string,Type:string, TrafficLightProtocolLevel:string, ActivityGroupNames:string)[@"https://raw.githubusercontent.com/microsoft/mstic/master/RapidReleaseTI/Indicators.csv"] with(format="csv", ignoreFirstRecord=True);
//Create a list of TLDs in our threat feed for later validation
let list_tlds = ThreatIntelligenceIndicator
| where TimeGenerated > ago(ioc_lookBack)
| where isnotempty(DomainName)
| extend parts = split(DomainName, '.')
| extend tld = parts[(array_length(parts)-1)]
| summarize count() by tostring(tld)
| summarize make_list(tld);
let Domain_Indicators = (union isfuzzy=true
(ThreatIntelligenceIndicator
| where TimeGenerated >= ago(ioc_lookBack) and ExpirationDateTime > now()
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
| where Active == true
// Picking up only IOC's that contain the entities we want
| where isnotempty(DomainName)
| extend TI_DomainEntity = DomainName
),
(IoCList
| where IoC_Type =~ 'domainname'
| where ExpirationDateTime > now()
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IoC
| where Active =~ 'True'
| extend TI_DomainEntity = IoC
| project-away  IoC_Type
)
);
Domain_Indicators
// using innerunique to keep perf fast and result set low, we only need one match to indicate potential malicious activity that needs to be investigated
| join kind=innerunique (
  DnsEvents
  | where TimeGenerated > ago(dt_lookBack)
  //Extract domain patterns from syslog message
  | where isnotempty(Name)
  | extend parts = split(Name, '.')
  //Split out the TLD
  | extend tld = parts[(array_length(parts)-1)]
  //Validate parsed domain by checking if the TLD is in the list of TLDs in our threat feed
  | where tld in~ (list_tlds)
  | extend DNS_TimeGenerated = TimeGenerated
) on $left.TI_DomainEntity==$right.Name
| where DNS_TimeGenerated < ExpirationDateTime
| summarize DNS_TimeGenerated  = arg_max(DNS_TimeGenerated , *) by IndicatorId, Name, IoC
| project DNS_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, ExpirationDateTime, ConfidenceScore, Url, Computer, ClientIP, Name, QueryType, Type, IoC, TI_DomainEntity
| extend timestamp = DNS_TimeGenerated, HostCustomEntity = Computer, IPCustomEntity = ClientIP, URLCustomEntity = Url

version: 1.3.2
queryFrequency: 1h
requiredDataConnectors:
- connectorId: DNS
  dataTypes:
  - DnsEvents
- connectorId: ThreatIntelligence
  dataTypes:
  - ThreatIntelligenceIndicator
- connectorId: ThreatIntelligenceTaxii
  dataTypes:
  - ThreatIntelligenceIndicator
entityMappings:
- fieldMappings:
  - columnName: HostCustomEntity
    identifier: FullName
  entityType: Host
- fieldMappings:
  - columnName: IPCustomEntity
    identifier: Address
  entityType: IP
- fieldMappings:
  - columnName: URLCustomEntity
    identifier: Url
  entityType: URL
kind: Scheduled
queryPeriod: 14d
severity: Medium
query: |
  let dt_lookBack = 1h;
  let ioc_lookBack = 14d;
  let IoCList = externaldata(TimeGenerated:datetime,IoC:string,IoC_Type:string,ExpirationDateTime:datetime,Description:string,Action:string, ConfidenceScore:real, ThreatType:string, Active:string,Type:string, TrafficLightProtocolLevel:string, ActivityGroupNames:string)[@"https://raw.githubusercontent.com/microsoft/mstic/master/RapidReleaseTI/Indicators.csv"] with(format="csv", ignoreFirstRecord=True);
  //Create a list of TLDs in our threat feed for later validation
  let list_tlds = ThreatIntelligenceIndicator
  | where TimeGenerated > ago(ioc_lookBack)
  | where isnotempty(DomainName)
  | extend parts = split(DomainName, '.')
  | extend tld = parts[(array_length(parts)-1)]
  | summarize count() by tostring(tld)
  | summarize make_list(tld);
  let Domain_Indicators = (union isfuzzy=true
  (ThreatIntelligenceIndicator
  | where TimeGenerated >= ago(ioc_lookBack) and ExpirationDateTime > now()
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
  | where Active == true
  // Picking up only IOC's that contain the entities we want
  | where isnotempty(DomainName)
  | extend TI_DomainEntity = DomainName
  ),
  (IoCList
  | where IoC_Type =~ 'domainname'
  | where ExpirationDateTime > now()
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IoC
  | where Active =~ 'True'
  | extend TI_DomainEntity = IoC
  | project-away  IoC_Type
  )
  );
  Domain_Indicators
  // using innerunique to keep perf fast and result set low, we only need one match to indicate potential malicious activity that needs to be investigated
  | join kind=innerunique (
    DnsEvents
    | where TimeGenerated > ago(dt_lookBack)
    //Extract domain patterns from syslog message
    | where isnotempty(Name)
    | extend parts = split(Name, '.')
    //Split out the TLD
    | extend tld = parts[(array_length(parts)-1)]
    //Validate parsed domain by checking if the TLD is in the list of TLDs in our threat feed
    | where tld in~ (list_tlds)
    | extend DNS_TimeGenerated = TimeGenerated
  ) on $left.TI_DomainEntity==$right.Name
  | where DNS_TimeGenerated < ExpirationDateTime
  | summarize DNS_TimeGenerated  = arg_max(DNS_TimeGenerated , *) by IndicatorId, Name, IoC
  | project DNS_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, ExpirationDateTime, ConfidenceScore, Url, Computer, ClientIP, Name, QueryType, Type, IoC, TI_DomainEntity
  | extend timestamp = DNS_TimeGenerated, HostCustomEntity = Computer, IPCustomEntity = ClientIP, URLCustomEntity = Url  
triggerOperator: gt
id: 85aca4d1-5d15-4001-abd9-acb86ca1786a
description: |
    'Identifies a match in DnsEvents from any Domain IOC from TI'
triggerThreshold: 0
name: TI map Domain entity to DnsEvents
tactics:
- Impact
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat Intelligence/Analytic Rules/DomainEntity_DnsEvents.yaml

{
  "$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/85aca4d1-5d15-4001-abd9-acb86ca1786a')]",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/85aca4d1-5d15-4001-abd9-acb86ca1786a')]",
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules",
      "kind": "Scheduled",
      "apiVersion": "2022-11-01",
      "properties": {
        "displayName": "TI map Domain entity to DnsEvents",
        "description": "'Identifies a match in DnsEvents from any Domain IOC from TI'\n",
        "severity": "Medium",
        "enabled": true,
        "query": "let dt_lookBack = 1h;\nlet ioc_lookBack = 14d;\nlet IoCList = externaldata(TimeGenerated:datetime,IoC:string,IoC_Type:string,ExpirationDateTime:datetime,Description:string,Action:string, ConfidenceScore:real, ThreatType:string, Active:string,Type:string, TrafficLightProtocolLevel:string, ActivityGroupNames:string)[@\"https://raw.githubusercontent.com/microsoft/mstic/master/RapidReleaseTI/Indicators.csv\"] with(format=\"csv\", ignoreFirstRecord=True);\n//Create a list of TLDs in our threat feed for later validation\nlet list_tlds = ThreatIntelligenceIndicator\n| where TimeGenerated > ago(ioc_lookBack)\n| where isnotempty(DomainName)\n| extend parts = split(DomainName, '.')\n| extend tld = parts[(array_length(parts)-1)]\n| summarize count() by tostring(tld)\n| summarize make_list(tld);\nlet Domain_Indicators = (union isfuzzy=true\n(ThreatIntelligenceIndicator\n| where TimeGenerated >= ago(ioc_lookBack) and ExpirationDateTime > now()\n| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId\n| where Active == true\n// Picking up only IOC's that contain the entities we want\n| where isnotempty(DomainName)\n| extend TI_DomainEntity = DomainName\n),\n(IoCList\n| where IoC_Type =~ 'domainname'\n| where ExpirationDateTime > now()\n| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IoC\n| where Active =~ 'True'\n| extend TI_DomainEntity = IoC\n| project-away  IoC_Type\n)\n);\nDomain_Indicators\n// using innerunique to keep perf fast and result set low, we only need one match to indicate potential malicious activity that needs to be investigated\n| join kind=innerunique (\n  DnsEvents\n  | where TimeGenerated > ago(dt_lookBack)\n  //Extract domain patterns from syslog message\n  | where isnotempty(Name)\n  | extend parts = split(Name, '.')\n  //Split out the TLD\n  | extend tld = parts[(array_length(parts)-1)]\n  //Validate parsed domain by checking if the TLD is in the list of TLDs in our threat feed\n  | where tld in~ (list_tlds)\n  | extend DNS_TimeGenerated = TimeGenerated\n) on $left.TI_DomainEntity==$right.Name\n| where DNS_TimeGenerated < ExpirationDateTime\n| summarize DNS_TimeGenerated  = arg_max(DNS_TimeGenerated , *) by IndicatorId, Name, IoC\n| project DNS_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, ExpirationDateTime, ConfidenceScore, Url, Computer, ClientIP, Name, QueryType, Type, IoC, TI_DomainEntity\n| extend timestamp = DNS_TimeGenerated, HostCustomEntity = Computer, IPCustomEntity = ClientIP, URLCustomEntity = Url\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "P14D",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0,
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Impact"
        ],
        "alertRuleTemplateName": "85aca4d1-5d15-4001-abd9-acb86ca1786a",
        "customDetails": null,
        "entityMappings": [
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "identifier": "FullName",
                "columnName": "HostCustomEntity"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "identifier": "Address",
                "columnName": "IPCustomEntity"
              }
            ]
          },
          {
            "entityType": "URL",
            "fieldMappings": [
              {
                "identifier": "Url",
                "columnName": "URLCustomEntity"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat Intelligence/Analytic Rules/DomainEntity_DnsEvents.yaml",
        "templateVersion": "1.3.2"
      }
    }
  ]
}