TI map Email entity to SigninLogs

id: 30fa312c-31eb-43d8-b0cc-bcbdfb360822
name: TI map Email entity to SigninLogs
description: |
  'Identifies a match in SigninLogs table from any Email IOC from TI'
severity: Medium
requiredDataConnectors:
  - connectorId: ThreatIntelligence
    dataTypes:
      - ThreatIntelligenceIndicator
  - connectorId: ThreatIntelligenceTaxii
    dataTypes:
      - ThreatIntelligenceIndicator
  - connectorId: AzureActiveDirectory
    dataTypes:
      - SigninLogs
  - connectorId: AzureActiveDirectory
    dataTypes:
      - AADNonInteractiveUserSignInLogs
  - connectorId: MicrosoftDefenderThreatIntelligence
    dataTypes:
      - ThreatIntelligenceIndicator
queryFrequency: 1h
queryPeriod: 14d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - InitialAccess
relevantTechniques:
  - T1566
query: |
  let dt_lookBack = 1h;
  let ioc_lookBack = 14d;
  let emailregex = @'^[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+$';
  let Signins = materialize(union isfuzzy=true
  ( SigninLogs | where TimeGenerated >= ago(dt_lookBack)),
  ( AADNonInteractiveUserSignInLogs | where TimeGenerated >= ago(dt_lookBack)
      | extend Status = todynamic(Status), LocationDetails = todynamic(LocationDetails))
  | where isnotempty(UserPrincipalName) and UserPrincipalName matches regex emailregex
  | extend UserPrincipalName = tolower(UserPrincipalName)
  | extend Status = todynamic(Status), LocationDetails = todynamic(LocationDetails)
  | extend StatusCode = tostring(Status.errorCode), StatusDetails = tostring(Status.additionalDetails)
  | extend State = tostring(LocationDetails.state), City = tostring(LocationDetails.city), Region = tostring(LocationDetails.countryOrRegion)
  | extend SigninLogs_TimeGenerated = TimeGenerated);
  let SigninUPNs = Signins | distinct UserPrincipalName | summarize make_list(UserPrincipalName);
  ThreatIntelligenceIndicator
  //Filtering the table for Email related IOCs
  | where isnotempty(EmailSenderAddress)
  | where TimeGenerated >= ago(ioc_lookBack)
  | where EmailSenderAddress in (SigninUPNs)
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
  | where Active == true and ExpirationDateTime > now()
  | where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;"
  | join kind=innerunique (Signins) on $left.EmailSenderAddress == $right.UserPrincipalName
  | where SigninLogs_TimeGenerated < ExpirationDateTime
  | summarize SigninLogs_TimeGenerated = arg_max(SigninLogs_TimeGenerated, *) by IndicatorId, UserPrincipalName
  | project SigninLogs_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, ExpirationDateTime, ConfidenceScore, EmailSenderName, EmailRecipient, EmailSourceDomain, EmailSourceIpAddress, EmailSubject, FileHashValue, FileHashType, IPAddress, UserPrincipalName, AppDisplayName, StatusCode, StatusDetails, NetworkIP, NetworkDestinationIP, NetworkSourceIP, Type
  | extend Name = tostring(split(UserPrincipalName, '@', 0)[0]), UPNSuffix = tostring(split(UserPrincipalName, '@', 1)[0])
  | extend timestamp = SigninLogs_TimeGenerated
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: FullName
        columnName: UserPrincipalName
      - identifier: Name
        columnName: Name
      - identifier: UPNSuffix
        columnName: UPNSuffix 
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: IPAddress
  - entityType: URL
    fieldMappings:
      - identifier: Url
        columnName: Url
version: 1.2.7
kind: Scheduled