TI Map IP entity to DNS Events ASIM DNS schema

let dt_lookBack = 1h;
let ioc_lookBack = 14d;
let IP_TI = 
ThreatIntelIndicators
| where TimeGenerated >= ago(ioc_lookBack)
//extract key part of kv pair
| extend IndicatorType = replace(@"\[|\]|\""", "", tostring(split(ObservableKey, ":", 0)))
| where IndicatorType == "ipv4-addr"
| extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
| extend NetworkSourceIP = ObservableValue
| extend IoC = NetworkSourceIP
| extend IndicatorId = tostring(split(Id, "--")[2])
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
| where IsActive and (ValidUntil > now() or isempty(ValidUntil));
IP_TI
 | project-reorder *, IsActive, Tags, TrafficLightProtocolLevel, NetworkSourceIP, Type, IoC
| join kind=innerunique // 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
(
_Im_Dns(starttime=ago(dt_lookBack))
| where isnotempty(DnsResponseName)
| summarize imDns_mintime=min(TimeGenerated), imDns_maxtime=max(TimeGenerated) by SrcIpAddr, DnsQuery, DnsResponseName, Dvc, EventProduct, EventVendor
| extend addresses = extract_all (@'(\d+\.\d+\.\d+\.\d+)', DnsResponseName)
| mv-expand IoC = addresses to typeof(string)
)
on IoC
| where imDns_mintime < ValidUntil
| extend Description = tostring(parse_json(Data).description)
| extend ActivityGroupNames = extract(@"ActivityGroup:(\S+)", 1, tostring(parse_json(Data).labels))
| extend ThreatType = tostring(Data.indicator_types[0])
| project imDns_mintime, imDns_maxtime, Description, ActivityGroupNames, IndicatorId, ThreatType, LatestIndicatorTime, ValidUntil, Confidence, 
SrcIpAddr, IoC, Dvc, EventVendor, EventProduct, DnsQuery, DnsResponseName, Type

name: TI Map IP entity to DNS Events (ASIM DNS schema)
triggerOperator: gt
query: |
  let dt_lookBack = 1h;
  let ioc_lookBack = 14d;
  let IP_TI = 
  ThreatIntelIndicators
  | where TimeGenerated >= ago(ioc_lookBack)
  //extract key part of kv pair
  | extend IndicatorType = replace(@"\[|\]|\""", "", tostring(split(ObservableKey, ":", 0)))
  | where IndicatorType == "ipv4-addr"
  | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
  | extend NetworkSourceIP = ObservableValue
  | extend IoC = NetworkSourceIP
  | extend IndicatorId = tostring(split(Id, "--")[2])
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
  | where IsActive and (ValidUntil > now() or isempty(ValidUntil));
  IP_TI
   | project-reorder *, IsActive, Tags, TrafficLightProtocolLevel, NetworkSourceIP, Type, IoC
  | join kind=innerunique // 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
  (
  _Im_Dns(starttime=ago(dt_lookBack))
  | where isnotempty(DnsResponseName)
  | summarize imDns_mintime=min(TimeGenerated), imDns_maxtime=max(TimeGenerated) by SrcIpAddr, DnsQuery, DnsResponseName, Dvc, EventProduct, EventVendor
  | extend addresses = extract_all (@'(\d+\.\d+\.\d+\.\d+)', DnsResponseName)
  | mv-expand IoC = addresses to typeof(string)
  )
  on IoC
  | where imDns_mintime < ValidUntil
  | extend Description = tostring(parse_json(Data).description)
  | extend ActivityGroupNames = extract(@"ActivityGroup:(\S+)", 1, tostring(parse_json(Data).labels))
  | extend ThreatType = tostring(Data.indicator_types[0])
  | project imDns_mintime, imDns_maxtime, Description, ActivityGroupNames, IndicatorId, ThreatType, LatestIndicatorTime, ValidUntil, Confidence, 
  SrcIpAddr, IoC, Dvc, EventVendor, EventProduct, DnsQuery, DnsResponseName, Type
queryFrequency: 1h
description: |
  'This rule identifies DNS requests for which response IP address is a known IoC. This analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM DNS schema.'
id: b306fba8-1a28-449f-aa24-30362e16d4f5
triggerThreshold: 0
queryPeriod: 14d
version: 1.2.11
kind: Scheduled
customDetails:
  DNSRequestTime: imDns_mintime
  IndicatorId: IndicatorId
  Description: Description
  ThreatType: ThreatType
  ActivityGroupNames: ActivityGroupNames
  ExpirationDateTime: ValidUntil
  LatestIndicatorTime: LatestIndicatorTime
  DnsQuery: DnsQuery
  ConfidenceScore: Confidence
  SourceIPAddress: SrcIpAddr
relevantTechniques:
- T1071
tags:
- ParentAlert: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ThreatIntelligenceIndicator/IPEntity_DnsEvents.yaml
  version: 1.0.0
- SchemaVersion: 0.1.1
  Schema: ASIMDns
severity: Medium
requiredDataConnectors:
- connectorId: ThreatIntelligence
  dataTypes:
  - ThreatIntelIndicators
- connectorId: ThreatIntelligenceTaxii
  dataTypes:
  - ThreatIntelIndicators
- 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: CiscoUmbrellaDataConnector
  dataTypes:
  - Cisco_Umbrella_dns_CL
- connectorId: MicrosoftDefenderThreatIntelligence
  dataTypes:
  - ThreatIntelIndicators
- connectorId: Corelight
  dataTypes:
  - Corelight_CL
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat%20Intelligence%20%28NEW%29/Analytic%20Rules/imDns_IPEntity_DnsEvents.yaml
alertDetailsOverride:
  alertDescriptionFormat: The response address {{IoC}} to a DNS query matched a known indicator of compromise of {{ThreatType}}. Consult the threat intelligence blade for more information on the indicator.
  alertDisplayNameFormat: The response {{IoC}} to DNS query matched an IoC
tactics:
- CommandAndControl
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: Dvc
  entityType: Host
- fieldMappings:
  - identifier: Address
    columnName: IoC
  entityType: IP
- fieldMappings:
  - identifier: Address
    columnName: SrcIpAddr
  entityType: IP

{
  "$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/b306fba8-1a28-449f-aa24-30362e16d4f5')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/b306fba8-1a28-449f-aa24-30362e16d4f5')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "The response address {{IoC}} to a DNS query matched a known indicator of compromise of {{ThreatType}}. Consult the threat intelligence blade for more information on the indicator.",
          "alertDisplayNameFormat": "The response {{IoC}} to DNS query matched an IoC"
        },
        "alertRuleTemplateName": "b306fba8-1a28-449f-aa24-30362e16d4f5",
        "customDetails": {
          "ActivityGroupNames": "ActivityGroupNames",
          "ConfidenceScore": "Confidence",
          "Description": "Description",
          "DnsQuery": "DnsQuery",
          "DNSRequestTime": "imDns_mintime",
          "ExpirationDateTime": "ValidUntil",
          "IndicatorId": "IndicatorId",
          "LatestIndicatorTime": "LatestIndicatorTime",
          "SourceIPAddress": "SrcIpAddr",
          "ThreatType": "ThreatType"
        },
        "description": "'This rule identifies DNS requests for which response IP address is a known IoC. This 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 IP entity to DNS Events (ASIM DNS schema)",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "Dvc",
                "identifier": "FullName"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "IoC",
                "identifier": "Address"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "SrcIpAddr",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat%20Intelligence%20%28NEW%29/Analytic%20Rules/imDns_IPEntity_DnsEvents.yaml",
        "query": "let dt_lookBack = 1h;\nlet ioc_lookBack = 14d;\nlet IP_TI = \nThreatIntelIndicators\n| where TimeGenerated >= ago(ioc_lookBack)\n//extract key part of kv pair\n| extend IndicatorType = replace(@\"\\[|\\]|\\\"\"\", \"\", tostring(split(ObservableKey, \":\", 0)))\n| where IndicatorType == \"ipv4-addr\"\n| extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)\n| extend NetworkSourceIP = ObservableValue\n| extend IoC = NetworkSourceIP\n| extend IndicatorId = tostring(split(Id, \"--\")[2])\n| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue\n| where IsActive and (ValidUntil > now() or isempty(ValidUntil));\nIP_TI\n | project-reorder *, IsActive, Tags, TrafficLightProtocolLevel, NetworkSourceIP, Type, IoC\n| join kind=innerunique // 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(\n_Im_Dns(starttime=ago(dt_lookBack))\n| where isnotempty(DnsResponseName)\n| summarize imDns_mintime=min(TimeGenerated), imDns_maxtime=max(TimeGenerated) by SrcIpAddr, DnsQuery, DnsResponseName, Dvc, EventProduct, EventVendor\n| extend addresses = extract_all (@'(\\d+\\.\\d+\\.\\d+\\.\\d+)', DnsResponseName)\n| mv-expand IoC = addresses to typeof(string)\n)\non IoC\n| where imDns_mintime < ValidUntil\n| extend Description = tostring(parse_json(Data).description)\n| extend ActivityGroupNames = extract(@\"ActivityGroup:(\\S+)\", 1, tostring(parse_json(Data).labels))\n| extend ThreatType = tostring(Data.indicator_types[0])\n| project imDns_mintime, imDns_maxtime, Description, ActivityGroupNames, IndicatorId, ThreatType, LatestIndicatorTime, ValidUntil, Confidence, \nSrcIpAddr, IoC, Dvc, EventVendor, EventProduct, DnsQuery, DnsResponseName, Type\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "P14D",
        "severity": "Medium",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "CommandAndControl"
        ],
        "tags": [
          {
            "ParentAlert": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ThreatIntelligenceIndicator/IPEntity_DnsEvents.yaml",
            "version": "1.0.0"
          },
          {
            "Schema": "ASIMDns",
            "SchemaVersion": "0.1.1"
          }
        ],
        "techniques": [
          "T1071"
        ],
        "templateVersion": "1.2.11",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}