GSA - TI Domain Entity

id: 4ef07345-5d89-4f5b-9c64-a180d81a6176
name: GSA - TI Domain Entity
description: |
  This query identifies Domain indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in GSA NetworkAccessTraffic.
severity: Medium
status: Available
requiredDataConnectors:
  - connectorId: AzureActiveDirectory
    dataTypes:
      - NetworkAccessTrafficLogs
queryFrequency: 1h
queryPeriod: 14d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - CommandAndControl
relevantTechniques:
  - T1071
query: |
  let dt_lookBack = 1h;
  let ioc_lookBack = 14d;
  let NetworkAccessTraff_ = NetworkAccessTraffic
  | where TimeGenerated >= ago(dt_lookBack)
  | where TrafficType == "internet"
  | where isnotempty(DestinationFqdn)
  | extend Domain = extract(@'([^.]+\.[^.]+)$', 1, DestinationFqdn)
  | project-rename GSANetworkAccessTraffic_TimeGenerated = TimeGenerated;
  let NetworkAccessTraffiDomains =
      NetworkAccessTraff_
      | distinct Domain;
  ThreatIntelIndicators
    | extend IndicatorType = replace(@'\[|\]|"""', "", tostring(split(ObservableKey, ":", 0)))
    | where IndicatorType == "domain-name"
    | extend DomainName = tolower(ObservableValue)
    | where TimeGenerated >= ago(ioc_lookBack)
    | extend IndicatorId = tostring(split(Id, "--")[2])
    | where DomainName in (NetworkAccessTraffiDomains)
    | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
    | where IsActive and (ValidUntil > now() or isempty(ValidUntil))
    | extend Description = tostring(parse_json(Data).description)
    | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
    | where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;"
    | project-reorder *, IsActive, Tags, TrafficLightProtocolLevel, DomainName, Type
    | join kind=innerunique (NetworkAccessTraff_) on $left.DomainName == $right.Domain
    | extend GSAThreatType = ThreatType
    | summarize GSANetworkAccessTraffic_TimeGenerated = arg_max(GSANetworkAccessTraffic_TimeGenerated, *) by Id, DestinationFqdn
    | project-reorder *,
      Tags,
      TrafficLightProtocolLevel,
      Type,
      DomainName,
      UserPrincipalName,
      UserId,
      DeviceId,
      InitiatingProcessName,
      GSAThreatType,
      DestinationUrl,
      DestinationPort,
      SourceIp,
      SourcePort,
      HttpUserAgent
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: UserPrincipalName
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: SourceIp
  - entityType: URL
    fieldMappings:
      - identifier: Url
        columnName: DestinationFqdn
  - entityType: Process
    fieldMappings:
      - identifier: CommandLine
        columnName: InitiatingProcessName
kind: Scheduled