TI map Domain entity to Dns Events ASIM DNS Schema

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 IndicatorType == "domain-name"
  | extend DomainName = ObservableValue
  | extend Url = iff(ObservableKey == "url:value", ObservableValue, "")
  
  | 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, ObservableValue
  | where IsActive and (ValidUntil > now() or isempty(ValidUntil));
let Domains = DomainTIs  |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)

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'  
kind: Scheduled
tactics:
- CommandAndControl
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: MicrosoftDefenderThreatIntelligence
  dataTypes:
  - ThreatIntelIndicators
- connectorId: CiscoUmbrellaDataConnector
  dataTypes:
  - Cisco_Umbrella_dns_CL
- connectorId: Corelight
  dataTypes:
  - Corelight_CL
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat Intelligence (NEW)/Analytic Rules/imDns_DomainEntity_DnsEvents.yaml
severity: Medium
name: TI map Domain entity to Dns Events (ASIM DNS Schema)
customDetails:
  ActivityGroupNames: ActivityGroupNames
  ExpirationDateTime: ValidUntil
  Description: Description
  DNSRequestTime: DNS_TimeGenerated
  IndicatorId: IndicatorId
  QueryType: DnsQueryType
  DnsQuery: DnsQuery
  LatestIndicatorTime: LatestIndicatorTime
  ConfidenceScore: Confidence
  SourceIPAddress: SrcIpAddr
triggerThreshold: 0
queryPeriod: 14d
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 IndicatorType == \"domain-name\"\n  | extend DomainName = ObservableValue\n  | extend Url = iff(ObservableKey == \"url:value\", ObservableValue, \"\")\n  \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, ObservableValue\n  | where IsActive and (ValidUntil > now() or isempty(ValidUntil));\nlet Domains = DomainTIs  |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"
relevantTechniques:
- T1071
id: 7c1ea2e6-6210-412c-92e4-180803a741b4
queryFrequency: 1h
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
triggerOperator: gt
version: 1.2.3
tags:
- Id: 85aca4d1-5d15-4001-abd9-acb86ca1786a
  version: 1.0.0
- Schema: ASIMDns
  SchemaVersion: 0.1.1