Bulk Changes to Privileged Account Permissions

let AdminRecords = AuditLogs
| where Category =~ "RoleManagement"
| where ActivityDisplayName has_any ("Add eligible member to role", "Add member to role")
| mv-apply TargetResource = TargetResources on 
  (
      where TargetResource.type =~ "User"
      | extend Target = tostring(TargetResource.userPrincipalName),
               props = TargetResource.modifiedProperties
  )
| mv-apply Property = props on 
  (
      where Property.displayName =~ "Role.DisplayName"
      | extend RoleName = trim('"',tostring(Property.newValue))
  )
| where RoleName contains "Admin";
AdminRecords
| summarize dcount(Target) by bin(TimeGenerated, 1h)
| where dcount_Target > 9
| join kind=rightsemi  (
  AdminRecords
  | extend TimeWindow = bin(TimeGenerated, 1h)
) on $left.TimeGenerated == $right.TimeWindow
| extend InitiatedByUser = iff(isnotempty(InitiatedBy.user.userPrincipalName), tostring(InitiatedBy.user.userPrincipalName), "")
| extend TargetName = tostring(split(Target,'@',0)[0]), TargetUPNSuffix = tostring(split(Target,'@',1)[0]),
         InitiatedByUserName = tostring(split(InitiatedByUser,'@',0)[0]), InitiatedByUserUPNSuffix = tostring(split(InitiatedByUser,'@',1)[0])

tactics:
- PrivilegeEscalation
severity: High
requiredDataConnectors:
- connectorId: AzureActiveDirectory
  dataTypes:
  - AuditLogs
triggerOperator: gt
tags:
- AADSecOpsGuide
query: |
  let AdminRecords = AuditLogs
  | where Category =~ "RoleManagement"
  | where ActivityDisplayName has_any ("Add eligible member to role", "Add member to role")
  | mv-apply TargetResource = TargetResources on 
    (
        where TargetResource.type =~ "User"
        | extend Target = tostring(TargetResource.userPrincipalName),
                 props = TargetResource.modifiedProperties
    )
  | mv-apply Property = props on 
    (
        where Property.displayName =~ "Role.DisplayName"
        | extend RoleName = trim('"',tostring(Property.newValue))
    )
  | where RoleName contains "Admin";
  AdminRecords
  | summarize dcount(Target) by bin(TimeGenerated, 1h)
  | where dcount_Target > 9
  | join kind=rightsemi  (
    AdminRecords
    | extend TimeWindow = bin(TimeGenerated, 1h)
  ) on $left.TimeGenerated == $right.TimeWindow
  | extend InitiatedByUser = iff(isnotempty(InitiatedBy.user.userPrincipalName), tostring(InitiatedBy.user.userPrincipalName), "")
  | extend TargetName = tostring(split(Target,'@',0)[0]), TargetUPNSuffix = tostring(split(Target,'@',1)[0]),
           InitiatedByUserName = tostring(split(InitiatedByUser,'@',0)[0]), InitiatedByUserUPNSuffix = tostring(split(InitiatedByUser,'@',1)[0])  
triggerThreshold: 0
name: Bulk Changes to Privileged Account Permissions
kind: Scheduled
version: 1.0.4
relevantTechniques:
- T1078.004
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Active Directory/Analytic Rules/BulkChangestoPrivilegedAccountPermissions.yaml
customDetails:
  InitiatedByUser: InitiatedByUser
  TargetUser: Target
description: |
  'Identifies when changes to multiple users permissions are changed at once. Investigate immediately if not a planned change. This setting could enable an attacker access to Azure subscriptions in your environment.
  Ref : https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-privileged-identity-management'  
status: Available
queryFrequency: 2h
queryPeriod: 2h
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: Name
    columnName: TargetName
  - identifier: UPNSuffix
    columnName: TargetUPNSuffix
- entityType: Account
  fieldMappings:
  - identifier: Name
    columnName: InitiatedByUserName
  - identifier: UPNSuffix
    columnName: InitiatedByUserUPNSuffix
id: 218f60de-c269-457a-b882-9966632b9dc6

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/218f60de-c269-457a-b882-9966632b9dc6')]",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/218f60de-c269-457a-b882-9966632b9dc6')]",
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules",
      "kind": "Scheduled",
      "apiVersion": "2022-11-01",
      "properties": {
        "displayName": "Bulk Changes to Privileged Account Permissions",
        "description": "'Identifies when changes to multiple users permissions are changed at once. Investigate immediately if not a planned change. This setting could enable an attacker access to Azure subscriptions in your environment.\nRef : https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-privileged-identity-management'\n",
        "severity": "High",
        "enabled": true,
        "query": "let AdminRecords = AuditLogs\n| where Category =~ \"RoleManagement\"\n| where ActivityDisplayName has_any (\"Add eligible member to role\", \"Add member to role\")\n| mv-apply TargetResource = TargetResources on \n  (\n      where TargetResource.type =~ \"User\"\n      | extend Target = tostring(TargetResource.userPrincipalName),\n               props = TargetResource.modifiedProperties\n  )\n| mv-apply Property = props on \n  (\n      where Property.displayName =~ \"Role.DisplayName\"\n      | extend RoleName = trim('\"',tostring(Property.newValue))\n  )\n| where RoleName contains \"Admin\";\nAdminRecords\n| summarize dcount(Target) by bin(TimeGenerated, 1h)\n| where dcount_Target > 9\n| join kind=rightsemi  (\n  AdminRecords\n  | extend TimeWindow = bin(TimeGenerated, 1h)\n) on $left.TimeGenerated == $right.TimeWindow\n| extend InitiatedByUser = iff(isnotempty(InitiatedBy.user.userPrincipalName), tostring(InitiatedBy.user.userPrincipalName), \"\")\n| extend TargetName = tostring(split(Target,'@',0)[0]), TargetUPNSuffix = tostring(split(Target,'@',1)[0]),\n         InitiatedByUserName = tostring(split(InitiatedByUser,'@',0)[0]), InitiatedByUserUPNSuffix = tostring(split(InitiatedByUser,'@',1)[0])\n",
        "queryFrequency": "PT2H",
        "queryPeriod": "PT2H",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0,
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "PrivilegeEscalation"
        ],
        "techniques": [
          "T1078.004"
        ],
        "alertRuleTemplateName": "218f60de-c269-457a-b882-9966632b9dc6",
        "customDetails": {
          "InitiatedByUser": "InitiatedByUser",
          "TargetUser": "Target"
        },
        "entityMappings": [
          {
            "fieldMappings": [
              {
                "columnName": "TargetName",
                "identifier": "Name"
              },
              {
                "columnName": "TargetUPNSuffix",
                "identifier": "UPNSuffix"
              }
            ],
            "entityType": "Account"
          },
          {
            "fieldMappings": [
              {
                "columnName": "InitiatedByUserName",
                "identifier": "Name"
              },
              {
                "columnName": "InitiatedByUserUPNSuffix",
                "identifier": "UPNSuffix"
              }
            ],
            "entityType": "Account"
          }
        ],
        "tags": [
          "AADSecOpsGuide"
        ],
        "status": "Available",
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Active Directory/Analytic Rules/BulkChangestoPrivilegedAccountPermissions.yaml",
        "templateVersion": "1.0.4"
      }
    }
  ]
}