TI map Domain entity to Dns Events ASIM DNS Schema

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Id	999e9f5d-db4a-4b07-a206-29c4e667b7e8
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/Analytic Rules/imDns_DomainEntity_DnsEvents.yaml
Version	1.1.8
Arm template	999e9f5d-db4a-4b07-a206-29c4e667b7e8.json

KQL

let HAS_ANY_MAX = 10000;
let dt_lookBack = 1h;
let ioc_lookBack = 14d;
let DomainTIs= ThreatIntelligenceIndicator
  // Picking up only IOC's that contain the entities we want
  | where isnotempty(DomainName)
  | where TimeGenerated >= ago(ioc_lookBack)
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
  | where Active == true and ExpirationDateTime > 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
  | join (
      _Im_Dns(starttime=ago(dt_lookBack), domain_has_any=toscalar(Domains))
      | extend DNS_TimeGenerated = TimeGenerated
) on $left.DomainName==$right.DnsQuery
| where DNS_TimeGenerated < ExpirationDateTime
| project LatestIndicatorTime, Description, ActivityGroupNames, IndicatorId, ThreatType, ExpirationDateTime, ConfidenceScore, Url, DNS_TimeGenerated, Dvc, SrcIpAddr, Domain, DnsQuery, DnsQueryType
| extend HostName = tostring(split(Dvc, ".")[0]), DomainIndex = toint(indexof(Dvc, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)

YAML

OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat Intelligence/Analytic Rules/imDns_DomainEntity_DnsEvents.yaml
requiredDataConnectors:
- dataTypes:
  - ThreatIntelligenceIndicator
  connectorId: ThreatIntelligence
- dataTypes:
  - ThreatIntelligenceIndicator
  connectorId: ThreatIntelligenceTaxii
- dataTypes:
  - DnsEvents
  connectorId: DNS
- dataTypes:
  - AzureDiagnostics
  connectorId: AzureFirewall
- dataTypes:
  - CommonSecurityLog
  connectorId: Zscaler
- dataTypes:
  - Syslog
  connectorId: InfobloxNIOS
- dataTypes:
  - GCP_DNS_CL
  connectorId: GCPDNSDataConnector
- dataTypes:
  - NXLog_DNS_Server_CL
  connectorId: NXLogDnsLogs
- dataTypes:
  - ThreatIntelligenceIndicator
  connectorId: MicrosoftDefenderThreatIntelligence
- dataTypes:
  - Cisco_Umbrella_dns_CL
  connectorId: CiscoUmbrellaDataConnector
- dataTypes:
  - Corelight_CL
  connectorId: Corelight
customDetails:
  ActivityGroupNames: ActivityGroupNames
  LatestIndicatorTime: LatestIndicatorTime
  ThreatType: ThreatType
  IndicatorId: IndicatorId
  DNSRequestTime: DNS_TimeGenerated
  ExpirationDateTime: ExpirationDateTime
  DnsQuery: DnsQuery
  QueryType: DnsQueryType
  ConfidenceScore: ConfidenceScore
  SourceIPAddress: SrcIpAddr
  Description: Description
name: TI map Domain entity to Dns Events (ASIM DNS Schema)
entityMappings:
- fieldMappings:
  - columnName: Dvc
    identifier: FullName
  - columnName: HostName
    identifier: HostName
  - columnName: HostNameDomain
    identifier: DnsDomain
  entityType: Host
- fieldMappings:
  - columnName: SrcIpAddr
    identifier: Address
  entityType: IP
- fieldMappings:
  - columnName: Url
    identifier: Url
  entityType: URL
- fieldMappings:
  - columnName: Domain
    identifier: DomainName
  entityType: DNS
id: 999e9f5d-db4a-4b07-a206-29c4e667b7e8
tags:
- Id: 85aca4d1-5d15-4001-abd9-acb86ca1786a
  version: 1.0.0
- Schema: ASIMDns
  SchemaVersion: 0.1.1
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'  
tactics:
- CommandAndControl
triggerThreshold: 0
kind: Scheduled
query: |
  let HAS_ANY_MAX = 10000;
  let dt_lookBack = 1h;
  let ioc_lookBack = 14d;
  let DomainTIs= ThreatIntelligenceIndicator
    // Picking up only IOC's that contain the entities we want
    | where isnotempty(DomainName)
    | where TimeGenerated >= ago(ioc_lookBack)
    | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
    | where Active == true and ExpirationDateTime > 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
    | join (
        _Im_Dns(starttime=ago(dt_lookBack), domain_has_any=toscalar(Domains))
        | extend DNS_TimeGenerated = TimeGenerated
  ) on $left.DomainName==$right.DnsQuery
  | where DNS_TimeGenerated < ExpirationDateTime
  | project LatestIndicatorTime, Description, ActivityGroupNames, IndicatorId, ThreatType, ExpirationDateTime, ConfidenceScore, Url, DNS_TimeGenerated, Dvc, SrcIpAddr, Domain, DnsQuery, DnsQueryType
  | extend HostName = tostring(split(Dvc, ".")[0]), DomainIndex = toint(indexof(Dvc, '.'))
  | extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)  
triggerOperator: gt
queryPeriod: 14d
queryFrequency: 1h
version: 1.1.8
severity: Medium
relevantTechniques:
- T1071

ARM