TI Map IP Entity to VMConnection

id: 9713e3c0-1410-468d-b79e-383448434b2d
name: TI Map IP Entity to VMConnection
description: |
  This query maps any IP indicators of compromise (IOCs) from threat intelligence (TI), by searching for matches in VMConnection.
severity: Medium
requiredDataConnectors:
  - connectorId: ThreatIntelligence
    dataTypes:
      - ThreatIntelligenceIndicator
  - connectorId: ThreatIntelligenceTaxii
    dataTypes:
      - ThreatIntelligenceIndicator
  - connectorId: MicrosoftDefenderThreatIntelligence
    dataTypes:
      - ThreatIntelligenceIndicator
  - connectorId: AzureMonitor(VMInsights)
    dataTypes:
      - VMConnection
queryFrequency: 1h
queryPeriod: 14d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - CommandAndControl
relevantTechniques:
  - T1071
query: |
  let dt_lookBack = 1h; // Look back 1 hour for VMConnection events
  let ioc_lookBack = 14d; // Look back 14 days for threat intelligence indicators
  // Fetch threat intelligence indicators related to IP addresses
  let IP_Indicators = ThreatIntelligenceIndicator
    | where isnotempty(NetworkIP) or isnotempty(EmailSourceIpAddress) or isnotempty(NetworkDestinationIP) or isnotempty(NetworkSourceIP)
    | where TimeGenerated >= ago(ioc_lookBack)
    | extend TI_ipEntity = iff(isnotempty(NetworkIP), NetworkIP, NetworkDestinationIP)
    | extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(NetworkSourceIP), NetworkSourceIP, TI_ipEntity)
    | extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(EmailSourceIpAddress), EmailSourceIpAddress, TI_ipEntity)
    | where ipv4_is_private(TI_ipEntity) == false and  TI_ipEntity !startswith "fe80" and TI_ipEntity !startswith "::" and TI_ipEntity !startswith "127."
    | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
    | where Active == true and ExpirationDateTime > now();
  // Perform a join between IP indicators and VMConnection events
  IP_Indicators
    // Use innerunique to keep performance fast and result set low, as we only need one match to indicate potential malicious activity that needs investigation
    | join kind=innerunique (
        VMConnection
        | where TimeGenerated >= ago(dt_lookBack)
        | extend VMConnection_TimeGenerated = TimeGenerated
    )
    on $left.TI_ipEntity == $right.RemoteIp
    // Filter out VMConnection events that occurred after the expiration of the corresponding indicator
    | where VMConnection_TimeGenerated < ExpirationDateTime
    // Group the results by IndicatorId and keep the VMConnection event with the latest timestamp
    | summarize VMConnection_TimeGenerated = arg_max(VMConnection_TimeGenerated, *) by IndicatorId, RemoteIp
    // Select the desired output fields
    | project VMConnection_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, ExpirationDateTime, ConfidenceScore,
      TI_ipEntity, Computer, Direction, ProcessName, SourceIp, DestinationIp, RemoteIp, Protocol, DestinationPort, NetworkIP, NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress, Type
    | extend timestamp = VMConnection_TimeGenerated, HostName = tostring(split(Computer, '.', 0)[0]), DnsDomain = tostring(strcat_array(array_slice(split(Computer, '.'), 1, -1), '.'))
entityMappings:
  - entityType: Host
    fieldMappings:
      - identifier: HostName
        columnName: HostName
      - identifier: DnsDomain
        columnName: DnsDomain
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: RemoteIp
  - entityType: URL
    fieldMappings:
      - identifier: Url
        columnName: Url
version: 1.4.2
kind: Scheduled