TI Map IP Entity to Azure SQL Security Audit Events

Original query, unchanged.

let dt_lookBack = 1h; // Look back 1 hour for AzureDiagnostics logs
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 AzureDiagnostics logs for SQL Security Audit 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 (
      AzureDiagnostics
      | where TimeGenerated >= ago(dt_lookBack)
      | where ResourceProvider == 'MICROSOFT.SQL'
      | where Category == 'SQLSecurityAuditEvents'
      | extend SQLSecurityAuditEvents_TimeGenerated = TimeGenerated
      | extend ClientIP = column_ifexists("client_ip_s", "Not Available")
      | extend Action = column_ifexists("action_name_s", "Not Available")
      | extend Application = column_ifexists("application_name_s", "Not Available")
      | extend HostName = column_ifexists("host_name_s", "Not Available")
  )
  on $left.TI_ipEntity == $right.ClientIP
  // Filter out logs that occurred after the expiration of the corresponding indicator
  | where SQLSecurityAuditEvents_TimeGenerated < ExpirationDateTime
  // Group the results by IndicatorId and ClientIP, and keep the log entry with the latest timestamp
  | summarize SQLSecurityAuditEvents_TimeGenerated = arg_max(SQLSecurityAuditEvents_TimeGenerated, *) by IndicatorId, ClientIP
  // Select the desired output fields
  | project SQLSecurityAuditEvents_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, ExpirationDateTime, ConfidenceScore,
    TI_ipEntity, ResourceId, ClientIP, Action, Application, HostName, NetworkIP, NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress, Type
  // Rename the timestamp field
  | extend timestamp = SQLSecurityAuditEvents_TimeGenerated