Unusual identity creation using exchange powershell | Microsoft Sentinel Analytic Rules

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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

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

ARM

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2024-01-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/0a3f4f4f-46ad-4562-acd6-f17730a5aef4')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/0a3f4f4f-46ad-4562-acd6-f17730a5aef4')]",
      "properties": {
        "alertRuleTemplateName": "0a3f4f4f-46ad-4562-acd6-f17730a5aef4",
        "customDetails": null,
        "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\n  Reference: https://www.microsoft.com/security/blog/2022/09/08/microsoft-investigates-iranian-attacks-against-the-albanian-government/'\n",
        "displayName": "Unusual identity creation using exchange powershell",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "InitiatingProcessAccount",
                "identifier": "FullName"
              },
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountDomain",
                "identifier": "NTDomain"
              }
            ]
          },
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "DeviceName",
                "identifier": "FullName"
              },
              {
                "columnName": "HostName",
                "identifier": "HostName"
              },
              {
                "columnName": "HostNameDomain",
                "identifier": "NTDomain"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/MultipleDataSources/EuropiumUnusualIdentity.yaml",
        "query": "(union isfuzzy=true\n(SecurityEvent\n| where EventID==4688\n| where CommandLine has_any (\"New-Mailbox\",\"Update-RoleGroupMember\") and CommandLine has \"HealthMailbox55x2yq\"\n| project TimeGenerated, DeviceName = Computer, AccountName = SubjectUserName, AccountDomain = SubjectDomainName, ProcessName, ProcessNameFullPath = NewProcessName, EventID, Activity, CommandLine, EventSourceName, Type\n| extend InitiatingProcessAccount = strcat(AccountDomain, \"\\\\\", AccountName)\n),\n(DeviceProcessEvents\n| where ProcessCommandLine has_any (\"New-Mailbox\",\"Update-RoleGroupMember\") and ProcessCommandLine has \"HealthMailbox55x2yq\"\n| extend timestamp = TimeGenerated, AccountDomain = InitiatingProcessAccountDomain, AccountName = InitiatingProcessAccountName\n| extend InitiatingProcessAccount = strcat(AccountDomain, \"\\\\\", AccountName)\n)\n)\n| extend HostName = tostring(split(DeviceName, \".\")[0]), DomainIndex = toint(indexof(DeviceName, '.'))\n| extend HostNameDomain = iff(DomainIndex != -1, substring(DeviceName, DomainIndex + 1), DeviceName)\n",
        "queryFrequency": "PT12H",
        "queryPeriod": "PT12H",
        "severity": "High",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Persistence"
        ],
        "tags": [
          "Europium"
        ],
        "techniques": [
          "T1136"
        ],
        "templateVersion": "1.1.1",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}