Unusual identity creation using exchange powershell

id: 0a3f4f4f-46ad-4562-acd6-f17730a5aef4
name: Unusual identity creation using exchange powershell
description: | 
  ' The query below identifies creation of unusual identity by the Europium actor to mimic Microsoft Exchange Health Manager Service account using Exchange PowerShell commands
    Reference: https://www.microsoft.com/security/blog/2022/09/08/microsoft-investigates-iranian-attacks-against-the-albanian-government/'
severity: High 
requiredDataConnectors:
  - connectorId: SecurityEvents
    dataTypes:
      - SecurityEvent
  - connectorId: MicrosoftThreatProtection
    dataTypes:
      - DeviceProcessEvents
queryFrequency: 12h 
queryPeriod: 12h 
triggerOperator: gt 
triggerThreshold: 0 
tactics: 
  - Persistence
relevantTechniques:
  - T1136
tags:
  - Europium
query: |
  (union isfuzzy=true
  (SecurityEvent
  | where EventID==4688
  | where CommandLine has_any ("New-Mailbox","Update-RoleGroupMember") and CommandLine has "HealthMailbox55x2yq"
  | project TimeGenerated, DeviceName = Computer, AccountName = SubjectUserName, AccountDomain = SubjectDomainName, ProcessName, ProcessNameFullPath = NewProcessName, EventID, Activity, CommandLine, EventSourceName, Type
  | extend InitiatingProcessAccount = strcat(AccountDomain, "\\", AccountName)
  ),
  (DeviceProcessEvents
  | where ProcessCommandLine has_any ("New-Mailbox","Update-RoleGroupMember") and ProcessCommandLine has "HealthMailbox55x2yq"
  | extend timestamp = TimeGenerated, AccountDomain = InitiatingProcessAccountDomain, AccountName = InitiatingProcessAccountName
  | extend InitiatingProcessAccount = strcat(AccountDomain, "\\", AccountName)
  )
  )
  | extend HostName = tostring(split(DeviceName, ".")[0]), DomainIndex = toint(indexof(DeviceName, '.'))
  | extend HostNameDomain = iff(DomainIndex != -1, substring(DeviceName, DomainIndex + 1), DeviceName)
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: FullName
        columnName: InitiatingProcessAccount
      - identifier: Name
        columnName: AccountName
      - identifier: NTDomain
        columnName: AccountDomain
  - entityType: Host
    fieldMappings:
      - identifier: FullName
        columnName: DeviceName
      - identifier: HostName
        columnName: HostName
      - identifier: NTDomain
        columnName: HostNameDomain
version: 1.1.1
kind: Scheduled
metadata:
    source:
        kind: Community
    author:
        name: Microsoft Security Research
    support:
        tier: Community
    categories:
        domains: [ "Security - Threat Protection", "Identity" ]