Unusual identity creation using exchange powershell

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Id	0a3f4f4f-46ad-4562-acd6-f17730a5aef4
Rulename	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
Tactics	Persistence
Techniques	T1136
Required data connectors	MicrosoftThreatProtection SecurityEvents
Kind	Scheduled
Query frequency	12h
Query period	12h
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Detections/MultipleDataSources/EuropiumUnusualIdentity.yaml
Version	1.1.1
Arm template	0a3f4f4f-46ad-4562-acd6-f17730a5aef4.json

KQL

(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)

YAML

version: 1.1.1
severity: High
tags:
- Europium
relevantTechniques:
- T1136
triggerOperator: gt
requiredDataConnectors:
- dataTypes:
  - SecurityEvent
  connectorId: SecurityEvents
- dataTypes:
  - DeviceProcessEvents
  connectorId: MicrosoftThreatProtection
queryFrequency: 12h
triggerThreshold: 0
entityMappings:
- fieldMappings:
  - columnName: InitiatingProcessAccount
    identifier: FullName
  - columnName: AccountName
    identifier: Name
  - columnName: AccountDomain
    identifier: NTDomain
  entityType: Account
- fieldMappings:
  - columnName: DeviceName
    identifier: FullName
  - columnName: HostName
    identifier: HostName
  - columnName: HostNameDomain
    identifier: NTDomain
  entityType: Host
metadata:
  categories:
    domains:
    - Security - Threat Protection
    - Identity
  author:
    name: Microsoft Security Research
  support:
    tier: Community
  source:
    kind: Community
id: 0a3f4f4f-46ad-4562-acd6-f17730a5aef4
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/'  
name: Unusual identity creation using exchange powershell
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)  
queryPeriod: 12h
tactics:
- Persistence
kind: Scheduled
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/MultipleDataSources/EuropiumUnusualIdentity.yaml

ARM