Network endpoint to host executable correlation

id: 01f64465-b1ef-41ea-a7f5-31553a11ad43
name: Network endpoint to host executable correlation
description: |
  'Correlates blocked URLs hosting [malicious] executables with host endpoint data to identify potential instances of executables of the same name having been recently run.
severity: Medium
status: Available
requiredDataConnectors:
  - connectorId: TrendMicro
    dataTypes:
      - CommonSecurityLog
  - connectorId: SecurityEvents
    dataTypes:
      - SecurityEvent
  - connectorId: WindowsSecurityEvents
    dataTypes: 
      - SecurityEvents 
  - connectorId: WindowsForwardedEvents
    dataTypes: 
      - WindowsEvent 
queryFrequency: 1d
queryPeriod: 1d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - Execution
relevantTechniques:
  - T1204
query: |
  let endpointData = 
  (union isfuzzy=true
  (SecurityEvent
    | where EventID == 4688
    | extend shortFileName = tolower(tostring(split(NewProcessName, '\\')[-1]))
    ),
    (WindowsEvent
    | where EventID == 4688
    | extend  NewProcessName = tostring(EventData.NewProcessName)
    | extend shortFileName = tolower(tostring(split(NewProcessName, '\\')[-1]))
    | extend TargetUserName = tostring(EventData.TargetUserName)
    ));
  // Correlate suspect executables seen in TrendMicro rule updates with similar activity on endpoints
  CommonSecurityLog
  | where DeviceVendor =~ "Trend Micro"
  | where Activity =~ "Deny List updated" 
  | where RequestURL endswith ".exe"
  | project TimeGenerated, Activity , RequestURL , SourceIP, DestinationIP
  | extend suspectExeName = tolower(tostring(split(RequestURL, '/')[-1]))
  | join kind=innerunique (endpointData) on $left.suspectExeName == $right.shortFileName 
  | extend HostName = tostring(split(Computer, '.', 0)[0]), DnsDomain = tostring(strcat_array(array_slice(split(Computer, '.'), 1, -1), '.'))
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: TargetUserName
  - entityType: Host
    fieldMappings:
      - identifier: HostName
        columnName: HostName
      - identifier: DnsDomain
        columnName: DnsDomain
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: DestinationIP
  - entityType: URL
    fieldMappings:
      - identifier: Url
        columnName: RequestURL
version: 1.1.6
kind: Scheduled