TI map Domain entity to Dns Events ASIM DNS Schema

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Id	7c1ea2e6-6210-412c-92e4-180803a741b4
Rulename	TI map Domain entity to Dns Events (ASIM DNS Schema)
Description	Identifies a match in DNS events from any Domain IOC from TI This analytic rule uses ASIM and supports any built-in or custom source that supports the ASIM DNS schema
Severity	Medium
Tactics	CommandAndControl
Techniques	T1071
Required data connectors	AzureFirewall CiscoUmbrellaDataConnector Corelight DNS GCPDNSDataConnector InfobloxNIOS MicrosoftDefenderThreatIntelligence NXLogDnsLogs ThreatIntelligence ThreatIntelligenceTaxii Zscaler
Kind	Scheduled
Query frequency	1h
Query period	14d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat Intelligence (NEW)/Analytic Rules/imDns_DomainEntity_DnsEvents.yaml
Version	1.2.1
Arm template	7c1ea2e6-6210-412c-92e4-180803a741b4.json

KQL

let HAS_ANY_MAX = 10000;
let dt_lookBack = 1h;
let ioc_lookBack = 14d;
let DomainTIs= ThreatIntelIndicators
  // Picking up only IOC's that contain the entities we want
  //extract key part of kv pair
  | extend IndicatorType = replace(@"\[|\]|\""", "", tostring(split(ObservableKey, ":", 0)))
  | extend IndicatorId = tostring(split(Id, "--")[2])
  | where isnotempty(IndicatorType) and IndicatorType == "domain-name"
  | extend DomainName = ObservableValue
  | extend Url = iff(ObservableKey == "url:value", ObservableValue, "")
  | where isnotempty(DomainName)
  | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
  | extend ThreatList = tostring(parse_json(Data).indicator_types[0])
  | where TimeGenerated >= ago(ioc_lookBack)
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
  | where IsActive == true and ValidUntil > now();
let Domains = DomainTIs | where isnotempty(DomainName) |summarize NDomains=dcount(DomainName), DomainsList=make_set(DomainName) 
  | project DomainList = iff(NDomains > HAS_ANY_MAX, dynamic([]), DomainsList);
DomainTIs
| project-reorder *, ThreatList, IsActive, Tags, TrafficLightProtocolLevel, DomainName, Type
  | join (
      _Im_Dns(starttime=ago(dt_lookBack), domain_has_any=toscalar(Domains))
      | extend DNS_TimeGenerated = TimeGenerated
) on $left.DomainName==$right.DnsQuery
| where DNS_TimeGenerated < ValidUntil
| extend Description = tostring(parse_json(Data).description)
| extend ActivityGroupNames = extract(@"ActivityGroup:(\S+)", 1, tostring(parse_json(Data).labels))
| project LatestIndicatorTime, Description, ActivityGroupNames, IndicatorId, ValidUntil, Confidence, DNS_TimeGenerated, Dvc, SrcIpAddr, Domain, DnsQuery, DnsQueryType, Url
| extend HostName = tostring(split(Dvc, ".")[0]), DomainIndex = toint(indexof(Dvc, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)

YAML

queryFrequency: 1h
requiredDataConnectors:
- connectorId: ThreatIntelligence
  dataTypes:
  - ThreatIntelligenceIndicator
- connectorId: ThreatIntelligenceTaxii
  dataTypes:
  - ThreatIntelligenceIndicator
- connectorId: DNS
  dataTypes:
  - DnsEvents
- connectorId: AzureFirewall
  dataTypes:
  - AzureDiagnostics
- connectorId: Zscaler
  dataTypes:
  - CommonSecurityLog
- connectorId: InfobloxNIOS
  dataTypes:
  - Syslog
- connectorId: GCPDNSDataConnector
  dataTypes:
  - GCP_DNS_CL
- connectorId: NXLogDnsLogs
  dataTypes:
  - NXLog_DNS_Server_CL
- connectorId: MicrosoftDefenderThreatIntelligence
  dataTypes:
  - ThreatIntelligenceIndicator
- connectorId: CiscoUmbrellaDataConnector
  dataTypes:
  - Cisco_Umbrella_dns_CL
- connectorId: Corelight
  dataTypes:
  - Corelight_CL
tags:
- Id: 85aca4d1-5d15-4001-abd9-acb86ca1786a
  version: 1.0.0
- Schema: ASIMDns
  SchemaVersion: 0.1.1
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat Intelligence (NEW)/Analytic Rules/imDns_DomainEntity_DnsEvents.yaml
query: |
  let HAS_ANY_MAX = 10000;
  let dt_lookBack = 1h;
  let ioc_lookBack = 14d;
  let DomainTIs= ThreatIntelIndicators
    // Picking up only IOC's that contain the entities we want
    //extract key part of kv pair
    | extend IndicatorType = replace(@"\[|\]|\""", "", tostring(split(ObservableKey, ":", 0)))
    | extend IndicatorId = tostring(split(Id, "--")[2])
    | where isnotempty(IndicatorType) and IndicatorType == "domain-name"
    | extend DomainName = ObservableValue
    | extend Url = iff(ObservableKey == "url:value", ObservableValue, "")
    | where isnotempty(DomainName)
    | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
    | extend ThreatList = tostring(parse_json(Data).indicator_types[0])
    | where TimeGenerated >= ago(ioc_lookBack)
    | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
    | where IsActive == true and ValidUntil > now();
  let Domains = DomainTIs | where isnotempty(DomainName) |summarize NDomains=dcount(DomainName), DomainsList=make_set(DomainName) 
    | project DomainList = iff(NDomains > HAS_ANY_MAX, dynamic([]), DomainsList);
  DomainTIs
  | project-reorder *, ThreatList, IsActive, Tags, TrafficLightProtocolLevel, DomainName, Type
    | join (
        _Im_Dns(starttime=ago(dt_lookBack), domain_has_any=toscalar(Domains))
        | extend DNS_TimeGenerated = TimeGenerated
  ) on $left.DomainName==$right.DnsQuery
  | where DNS_TimeGenerated < ValidUntil
  | extend Description = tostring(parse_json(Data).description)
  | extend ActivityGroupNames = extract(@"ActivityGroup:(\S+)", 1, tostring(parse_json(Data).labels))
  | project LatestIndicatorTime, Description, ActivityGroupNames, IndicatorId, ValidUntil, Confidence, DNS_TimeGenerated, Dvc, SrcIpAddr, Domain, DnsQuery, DnsQueryType, Url
  | extend HostName = tostring(split(Dvc, ".")[0]), DomainIndex = toint(indexof(Dvc, '.'))
  | extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)  
entityMappings:
- entityType: Host
  fieldMappings:
  - identifier: FullName
    columnName: Dvc
  - identifier: HostName
    columnName: HostName
  - identifier: DnsDomain
    columnName: HostNameDomain
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: SrcIpAddr
- entityType: URL
  fieldMappings:
  - identifier: Url
    columnName: Url
- entityType: DNS
  fieldMappings:
  - identifier: DomainName
    columnName: Domain
relevantTechniques:
- T1071
name: TI map Domain entity to Dns Events (ASIM DNS Schema)
description: |
  Identifies a match in DNS events from any Domain IOC from TI
  This analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM DNS schema'  
severity: Medium
queryPeriod: 14d
triggerOperator: gt
customDetails:
  ExpirationDateTime: ValidUntil
  ActivityGroupNames: ActivityGroupNames
  DnsQuery: DnsQuery
  DNSRequestTime: DNS_TimeGenerated
  QueryType: DnsQueryType
  Description: Description
  SourceIPAddress: SrcIpAddr
  ConfidenceScore: Confidence
  LatestIndicatorTime: LatestIndicatorTime
  IndicatorId: IndicatorId
kind: Scheduled
tactics:
- CommandAndControl
id: 7c1ea2e6-6210-412c-92e4-180803a741b4
version: 1.2.1
triggerThreshold: 0

ARM

{
  "$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/7c1ea2e6-6210-412c-92e4-180803a741b4')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/7c1ea2e6-6210-412c-92e4-180803a741b4')]",
      "properties": {
        "alertRuleTemplateName": "7c1ea2e6-6210-412c-92e4-180803a741b4",
        "customDetails": {
          "ActivityGroupNames": "ActivityGroupNames",
          "ConfidenceScore": "Confidence",
          "Description": "Description",
          "DnsQuery": "DnsQuery",
          "DNSRequestTime": "DNS_TimeGenerated",
          "ExpirationDateTime": "ValidUntil",
          "IndicatorId": "IndicatorId",
          "LatestIndicatorTime": "LatestIndicatorTime",
          "QueryType": "DnsQueryType",
          "SourceIPAddress": "SrcIpAddr"
        },
        "description": "Identifies a match in DNS events from any Domain IOC from TI\nThis analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM DNS schema'\n",
        "displayName": "TI map Domain entity to Dns Events (ASIM DNS Schema)",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "Dvc",
                "identifier": "FullName"
              },
              {
                "columnName": "HostName",
                "identifier": "HostName"
              },
              {
                "columnName": "HostNameDomain",
                "identifier": "DnsDomain"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "SrcIpAddr",
                "identifier": "Address"
              }
            ]
          },
          {
            "entityType": "URL",
            "fieldMappings": [
              {
                "columnName": "Url",
                "identifier": "Url"
              }
            ]
          },
          {
            "entityType": "DNS",
            "fieldMappings": [
              {
                "columnName": "Domain",
                "identifier": "DomainName"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat Intelligence (NEW)/Analytic Rules/imDns_DomainEntity_DnsEvents.yaml",
        "query": "let HAS_ANY_MAX = 10000;\nlet dt_lookBack = 1h;\nlet ioc_lookBack = 14d;\nlet DomainTIs= ThreatIntelIndicators\n  // Picking up only IOC's that contain the entities we want\n  //extract key part of kv pair\n  | extend IndicatorType = replace(@\"\\[|\\]|\\\"\"\", \"\", tostring(split(ObservableKey, \":\", 0)))\n  | extend IndicatorId = tostring(split(Id, \"--\")[2])\n  | where isnotempty(IndicatorType) and IndicatorType == \"domain-name\"\n  | extend DomainName = ObservableValue\n  | extend Url = iff(ObservableKey == \"url:value\", ObservableValue, \"\")\n  | where isnotempty(DomainName)\n  | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)\n  | extend ThreatList = tostring(parse_json(Data).indicator_types[0])\n  | where TimeGenerated >= ago(ioc_lookBack)\n  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId\n  | where IsActive == true and ValidUntil > now();\nlet Domains = DomainTIs | where isnotempty(DomainName) |summarize NDomains=dcount(DomainName), DomainsList=make_set(DomainName) \n  | project DomainList = iff(NDomains > HAS_ANY_MAX, dynamic([]), DomainsList);\nDomainTIs\n| project-reorder *, ThreatList, IsActive, Tags, TrafficLightProtocolLevel, DomainName, Type\n  | join (\n      _Im_Dns(starttime=ago(dt_lookBack), domain_has_any=toscalar(Domains))\n      | extend DNS_TimeGenerated = TimeGenerated\n) on $left.DomainName==$right.DnsQuery\n| where DNS_TimeGenerated < ValidUntil\n| extend Description = tostring(parse_json(Data).description)\n| extend ActivityGroupNames = extract(@\"ActivityGroup:(\\S+)\", 1, tostring(parse_json(Data).labels))\n| project LatestIndicatorTime, Description, ActivityGroupNames, IndicatorId, ValidUntil, Confidence, DNS_TimeGenerated, Dvc, SrcIpAddr, Domain, DnsQuery, DnsQueryType, Url\n| extend HostName = tostring(split(Dvc, \".\")[0]), DomainIndex = toint(indexof(Dvc, '.'))\n| extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "P14D",
        "severity": "Medium",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "CommandAndControl"
        ],
        "tags": [
          {
            "Id": "85aca4d1-5d15-4001-abd9-acb86ca1786a",
            "version": "1.0.0"
          },
          {
            "Schema": "ASIMDns",
            "SchemaVersion": "0.1.1"
          }
        ],
        "techniques": [
          "T1071"
        ],
        "templateVersion": "1.2.1",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}