New User Assigned to Privileged Role

// Define the start and end times based on input values
let starttime = now()-1h;
let endtime = now();
// Set a lookback period of 14 days
let lookback = starttime - 14d;
// Define a reusable function to query audit logs
let awsFunc = (start:datetime, end:datetime) {
  AuditLogs
  | where TimeGenerated between (start..end)
  | where Category =~ "RoleManagement"
  | where AADOperationType in ("Assign", "AssignEligibleRole")
  | where ActivityDisplayName has_any ("Add eligible member to role", "Add member to role")
  | mv-apply TargetResource = TargetResources on
    (
      where TargetResource.type in~ ("User", "ServicePrincipal")
      | extend Target = iff(TargetResource.type =~ "ServicePrincipal", tostring(TargetResource.displayName), 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" and Result == "success"
};
// Query for audit events in the current day
let EventInfo_CurrentDay = awsFunc(starttime, endtime);
// Query for audit events in the historical period (lookback)
let EventInfo_historical = awsFunc(lookback, starttime);
// Find unseen events by performing a left anti-join
let EventInfo_Unseen = (EventInfo_CurrentDay
  | join kind=leftanti(EventInfo_historical) on Target, RoleName, OperationName
);
// Extend and clean up the results
EventInfo_Unseen
| extend InitiatingAppName = tostring(InitiatedBy.app.displayName)
| extend InitiatingAppServicePrincipalId = tostring(InitiatedBy.app.servicePrincipalId)
| extend InitiatingUserPrincipalName = tostring(InitiatedBy.user.userPrincipalName)
| extend InitiatingAadUserId = tostring(InitiatedBy.user.id)
| extend InitiatingIpAddress = tostring(iff(isnotempty(InitiatedBy.user.ipAddress), InitiatedBy.user.ipAddress, InitiatedBy.app.ipAddress))
| extend Initiator = iif(isnotempty(InitiatingAppName), InitiatingAppName, InitiatingUserPrincipalName)
// You can uncomment the lines below to filter out PIM activations
// | where Initiator != "MS-PIM"
// | summarize StartTime=min(TimeGenerated), EndTime=min(TimeGenerated) by OperationName, RoleName, Target, Initiator, Result
// Project specific columns and split them for further analysis
| project TimeGenerated, OperationName, RoleName, Target, Initiator, InitiatingUserPrincipalName, InitiatingAadUserId, InitiatingAppName, InitiatingAppServicePrincipalId, InitiatingIpAddress, Result
| extend TargetName = tostring(split(Target,'@',0)[0]), TargetUPNSuffix = tostring(split(Target,'@',1)[0]), InitiatorName = tostring(split(InitiatingUserPrincipalName,'@',0)[0]), InitiatorUPNSuffix = tostring(split(InitiatingUserPrincipalName,'@',1)[0])

relevantTechniques:
- T1078.004
name: New User Assigned to Privileged Role
requiredDataConnectors:
- dataTypes:
  - AuditLogs
  connectorId: AzureActiveDirectory
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: Target
  - identifier: Name
    columnName: TargetName
  - identifier: UPNSuffix
    columnName: TargetUPNSuffix
  entityType: Account
- fieldMappings:
  - identifier: FullName
    columnName: InitiatingUserPrincipalName
  - identifier: Name
    columnName: InitiatorName
  - identifier: UPNSuffix
    columnName: InitiatorUPNSuffix
  entityType: Account
- fieldMappings:
  - identifier: AadUserId
    columnName: InitiatingAadUserId
  entityType: Account
- fieldMappings:
  - identifier: AadUserId
    columnName: InitiatingAppServicePrincipalId
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: InitiatingIpAddress
  entityType: IP
triggerThreshold: 0
id: 050b9b3d-53d0-4364-a3da-1b678b8211ec
tactics:
- Persistence
version: 1.1.0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Entra ID/Analytic Rules/UserAssignedPrivilegedRole.yaml
queryPeriod: 14d
kind: Scheduled
tags:
- AADSecOpsGuide
queryFrequency: 1h
severity: High
status: Available
description: |
    Identifies when a privileged role is assigned to a new user. Any account eligible for a role is now being given privileged access. If the assignment is unexpected or into a role that isn't the responsibility of the account holder, investigate.
query: |
  // Define the start and end times based on input values
  let starttime = now()-1h;
  let endtime = now();
  // Set a lookback period of 14 days
  let lookback = starttime - 14d;
  // Define a reusable function to query audit logs
  let awsFunc = (start:datetime, end:datetime) {
    AuditLogs
    | where TimeGenerated between (start..end)
    | where Category =~ "RoleManagement"
    | where AADOperationType in ("Assign", "AssignEligibleRole")
    | where ActivityDisplayName has_any ("Add eligible member to role", "Add member to role")
    | mv-apply TargetResource = TargetResources on
      (
        where TargetResource.type in~ ("User", "ServicePrincipal")
        | extend Target = iff(TargetResource.type =~ "ServicePrincipal", tostring(TargetResource.displayName), 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" and Result == "success"
  };
  // Query for audit events in the current day
  let EventInfo_CurrentDay = awsFunc(starttime, endtime);
  // Query for audit events in the historical period (lookback)
  let EventInfo_historical = awsFunc(lookback, starttime);
  // Find unseen events by performing a left anti-join
  let EventInfo_Unseen = (EventInfo_CurrentDay
    | join kind=leftanti(EventInfo_historical) on Target, RoleName, OperationName
  );
  // Extend and clean up the results
  EventInfo_Unseen
  | extend InitiatingAppName = tostring(InitiatedBy.app.displayName)
  | extend InitiatingAppServicePrincipalId = tostring(InitiatedBy.app.servicePrincipalId)
  | extend InitiatingUserPrincipalName = tostring(InitiatedBy.user.userPrincipalName)
  | extend InitiatingAadUserId = tostring(InitiatedBy.user.id)
  | extend InitiatingIpAddress = tostring(iff(isnotempty(InitiatedBy.user.ipAddress), InitiatedBy.user.ipAddress, InitiatedBy.app.ipAddress))
  | extend Initiator = iif(isnotempty(InitiatingAppName), InitiatingAppName, InitiatingUserPrincipalName)
  // You can uncomment the lines below to filter out PIM activations
  // | where Initiator != "MS-PIM"
  // | summarize StartTime=min(TimeGenerated), EndTime=min(TimeGenerated) by OperationName, RoleName, Target, Initiator, Result
  // Project specific columns and split them for further analysis
  | project TimeGenerated, OperationName, RoleName, Target, Initiator, InitiatingUserPrincipalName, InitiatingAadUserId, InitiatingAppName, InitiatingAppServicePrincipalId, InitiatingIpAddress, Result
  | extend TargetName = tostring(split(Target,'@',0)[0]), TargetUPNSuffix = tostring(split(Target,'@',1)[0]), InitiatorName = tostring(split(InitiatingUserPrincipalName,'@',0)[0]), InitiatorUPNSuffix = tostring(split(InitiatingUserPrincipalName,'@',1)[0])  
triggerOperator: gt

{
  "$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/050b9b3d-53d0-4364-a3da-1b678b8211ec')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/050b9b3d-53d0-4364-a3da-1b678b8211ec')]",
      "properties": {
        "alertRuleTemplateName": "050b9b3d-53d0-4364-a3da-1b678b8211ec",
        "customDetails": null,
        "description": "Identifies when a privileged role is assigned to a new user. Any account eligible for a role is now being given privileged access. If the assignment is unexpected or into a role that isn't the responsibility of the account holder, investigate.\n",
        "displayName": "New User Assigned to Privileged Role",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "Target",
                "identifier": "FullName"
              },
              {
                "columnName": "TargetName",
                "identifier": "Name"
              },
              {
                "columnName": "TargetUPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "InitiatingUserPrincipalName",
                "identifier": "FullName"
              },
              {
                "columnName": "InitiatorName",
                "identifier": "Name"
              },
              {
                "columnName": "InitiatorUPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "InitiatingAadUserId",
                "identifier": "AadUserId"
              }
            ]
          },
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "InitiatingAppServicePrincipalId",
                "identifier": "AadUserId"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "InitiatingIpAddress",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Entra ID/Analytic Rules/UserAssignedPrivilegedRole.yaml",
        "query": "// Define the start and end times based on input values\nlet starttime = now()-1h;\nlet endtime = now();\n// Set a lookback period of 14 days\nlet lookback = starttime - 14d;\n// Define a reusable function to query audit logs\nlet awsFunc = (start:datetime, end:datetime) {\n  AuditLogs\n  | where TimeGenerated between (start..end)\n  | where Category =~ \"RoleManagement\"\n  | where AADOperationType in (\"Assign\", \"AssignEligibleRole\")\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 in~ (\"User\", \"ServicePrincipal\")\n      | extend Target = iff(TargetResource.type =~ \"ServicePrincipal\", tostring(TargetResource.displayName), 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\" and Result == \"success\"\n};\n// Query for audit events in the current day\nlet EventInfo_CurrentDay = awsFunc(starttime, endtime);\n// Query for audit events in the historical period (lookback)\nlet EventInfo_historical = awsFunc(lookback, starttime);\n// Find unseen events by performing a left anti-join\nlet EventInfo_Unseen = (EventInfo_CurrentDay\n  | join kind=leftanti(EventInfo_historical) on Target, RoleName, OperationName\n);\n// Extend and clean up the results\nEventInfo_Unseen\n| extend InitiatingAppName = tostring(InitiatedBy.app.displayName)\n| extend InitiatingAppServicePrincipalId = tostring(InitiatedBy.app.servicePrincipalId)\n| extend InitiatingUserPrincipalName = tostring(InitiatedBy.user.userPrincipalName)\n| extend InitiatingAadUserId = tostring(InitiatedBy.user.id)\n| extend InitiatingIpAddress = tostring(iff(isnotempty(InitiatedBy.user.ipAddress), InitiatedBy.user.ipAddress, InitiatedBy.app.ipAddress))\n| extend Initiator = iif(isnotempty(InitiatingAppName), InitiatingAppName, InitiatingUserPrincipalName)\n// You can uncomment the lines below to filter out PIM activations\n// | where Initiator != \"MS-PIM\"\n// | summarize StartTime=min(TimeGenerated), EndTime=min(TimeGenerated) by OperationName, RoleName, Target, Initiator, Result\n// Project specific columns and split them for further analysis\n| project TimeGenerated, OperationName, RoleName, Target, Initiator, InitiatingUserPrincipalName, InitiatingAadUserId, InitiatingAppName, InitiatingAppServicePrincipalId, InitiatingIpAddress, Result\n| extend TargetName = tostring(split(Target,'@',0)[0]), TargetUPNSuffix = tostring(split(Target,'@',1)[0]), InitiatorName = tostring(split(InitiatingUserPrincipalName,'@',0)[0]), InitiatorUPNSuffix = tostring(split(InitiatingUserPrincipalName,'@',1)[0])\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "P14D",
        "severity": "High",
        "status": "Available",
        "subTechniques": [
          "T1078.004"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Persistence"
        ],
        "tags": [
          "AADSecOpsGuide"
        ],
        "techniques": [
          "T1078"
        ],
        "templateVersion": "1.1.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}