MailRead Permissions Granted to Application

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Id	2560515c-07d1-434e-87fb-ebe3af267760
Rulename	Mail.Read Permissions Granted to Application
Description	This query look for applications that have been granted (Delegated or App/Role) permissions to Read Mail (Permissions field has Mail.Read) and subsequently has been consented to. This can help identify applications that have been abused to gain access to mailboxes.
Severity	Medium
Tactics	Persistence
Techniques	T1098
Required data connectors	AzureActiveDirectory
Kind	Scheduled
Query frequency	1d
Query period	1d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Entra ID/Analytic Rules/MailPermissionsAddedToApplication.yaml
Version	1.0.4
Arm template	2560515c-07d1-434e-87fb-ebe3af267760.json

KQL

AuditLogs
| where Category =~ "ApplicationManagement"
| where ActivityDisplayName has_any ("Add delegated permission grant","Add app role assignment to service principal")  
| where Result =~ "success"
| where tostring(InitiatedBy.user.userPrincipalName) has "@" or tostring(InitiatedBy.app.displayName) has "@"
| mv-apply TargetResource = TargetResources on 
  (
      where TargetResource.type =~ "ServicePrincipal" and array_length(TargetResource.modifiedProperties) > 0 and isnotnull(TargetResource.displayName)
      | extend props = TargetResource.modifiedProperties,
               Type = tostring(TargetResource.type),
               PermissionsAddedTo = tostring(TargetResource.displayName)
  )
| mv-apply Property = props on 
  (
      where Property.displayName =~ "DelegatedPermissionGrant.Scope"
      | extend DisplayName = tostring(Property.displayName), Permissions = trim('"',tostring(Property.newValue))
  )
| where Permissions has_any ("Mail.Read", "Mail.ReadWrite")
| mv-apply AdditionalDetail = AdditionalDetails on 
  (
      where AdditionalDetail.key =~ "User-Agent"
      | extend InitiatingUserAgent = tostring(AdditionalDetail.value)
  )
| 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))
| project-away props, TargetResource, AdditionalDetail, Property
| join kind=leftouter(
  AuditLogs
  | where ActivityDisplayName has "Consent to application"
  | mv-apply TargetResource = TargetResources on 
      (
          where TargetResource.type =~ "ServicePrincipal"
          | extend AppName = tostring(TargetResource.displayName),
                   AppId = tostring(TargetResource.id)
      )
| project AppName, AppId, CorrelationId) on CorrelationId
| project-away CorrelationId1
| project-reorder TimeGenerated, OperationName, InitiatingUserPrincipalName, InitiatingAadUserId, InitiatingAppName, InitiatingAppServicePrincipalId, InitiatingIpAddress, InitiatingUserAgent, PermissionsAddedTo, Permissions, AppName, AppId, CorrelationId
| extend Name = tostring(split(InitiatingUserPrincipalName,'@',0)[0]), UPNSuffix = tostring(split(InitiatingUserPrincipalName,'@',1)[0])

YAML

id: 2560515c-07d1-434e-87fb-ebe3af267760
tactics:
- Persistence
queryPeriod: 1d
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Entra ID/Analytic Rules/MailPermissionsAddedToApplication.yaml
triggerThreshold: 0
name: Mail.Read Permissions Granted to Application
query: |
  AuditLogs
  | where Category =~ "ApplicationManagement"
  | where ActivityDisplayName has_any ("Add delegated permission grant","Add app role assignment to service principal")  
  | where Result =~ "success"
  | where tostring(InitiatedBy.user.userPrincipalName) has "@" or tostring(InitiatedBy.app.displayName) has "@"
  | mv-apply TargetResource = TargetResources on 
    (
        where TargetResource.type =~ "ServicePrincipal" and array_length(TargetResource.modifiedProperties) > 0 and isnotnull(TargetResource.displayName)
        | extend props = TargetResource.modifiedProperties,
                 Type = tostring(TargetResource.type),
                 PermissionsAddedTo = tostring(TargetResource.displayName)
    )
  | mv-apply Property = props on 
    (
        where Property.displayName =~ "DelegatedPermissionGrant.Scope"
        | extend DisplayName = tostring(Property.displayName), Permissions = trim('"',tostring(Property.newValue))
    )
  | where Permissions has_any ("Mail.Read", "Mail.ReadWrite")
  | mv-apply AdditionalDetail = AdditionalDetails on 
    (
        where AdditionalDetail.key =~ "User-Agent"
        | extend InitiatingUserAgent = tostring(AdditionalDetail.value)
    )
  | 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))
  | project-away props, TargetResource, AdditionalDetail, Property
  | join kind=leftouter(
    AuditLogs
    | where ActivityDisplayName has "Consent to application"
    | mv-apply TargetResource = TargetResources on 
        (
            where TargetResource.type =~ "ServicePrincipal"
            | extend AppName = tostring(TargetResource.displayName),
                     AppId = tostring(TargetResource.id)
        )
  | project AppName, AppId, CorrelationId) on CorrelationId
  | project-away CorrelationId1
  | project-reorder TimeGenerated, OperationName, InitiatingUserPrincipalName, InitiatingAadUserId, InitiatingAppName, InitiatingAppServicePrincipalId, InitiatingIpAddress, InitiatingUserAgent, PermissionsAddedTo, Permissions, AppName, AppId, CorrelationId
  | extend Name = tostring(split(InitiatingUserPrincipalName,'@',0)[0]), UPNSuffix = tostring(split(InitiatingUserPrincipalName,'@',1)[0])  
severity: Medium
triggerOperator: gt
kind: Scheduled
relevantTechniques:
- T1098
tags:
- Solorigate
- NOBELIUM
queryFrequency: 1d
requiredDataConnectors:
- connectorId: AzureActiveDirectory
  dataTypes:
  - AuditLogs
description: |
    'This query look for applications that have been granted (Delegated or App/Role) permissions to Read Mail (Permissions field has Mail.Read) and subsequently has been consented to. This can help identify applications that have been abused to gain access to mailboxes.'
status: Available
version: 1.0.4
entityMappings:
- fieldMappings:
  - columnName: InitiatingUserPrincipalName
    identifier: FullName
  - columnName: Name
    identifier: Name
  - columnName: UPNSuffix
    identifier: UPNSuffix
  entityType: Account
- fieldMappings:
  - columnName: InitiatingAadUserId
    identifier: AadUserId
  entityType: Account
- fieldMappings:
  - columnName: InitiatingAppServicePrincipalId
    identifier: AadUserId
  entityType: Account
- fieldMappings:
  - columnName: InitiatingIpAddress
    identifier: Address
  entityType: IP

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/2560515c-07d1-434e-87fb-ebe3af267760')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/2560515c-07d1-434e-87fb-ebe3af267760')]",
      "properties": {
        "alertRuleTemplateName": "2560515c-07d1-434e-87fb-ebe3af267760",
        "customDetails": null,
        "description": "'This query look for applications that have been granted (Delegated or App/Role) permissions to Read Mail (Permissions field has Mail.Read) and subsequently has been consented to. This can help identify applications that have been abused to gain access to mailboxes.'\n",
        "displayName": "Mail.Read Permissions Granted to Application",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "InitiatingUserPrincipalName",
                "identifier": "FullName"
              },
              {
                "columnName": "Name",
                "identifier": "Name"
              },
              {
                "columnName": "UPNSuffix",
                "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/MailPermissionsAddedToApplication.yaml",
        "query": "AuditLogs\n| where Category =~ \"ApplicationManagement\"\n| where ActivityDisplayName has_any (\"Add delegated permission grant\",\"Add app role assignment to service principal\")  \n| where Result =~ \"success\"\n| where tostring(InitiatedBy.user.userPrincipalName) has \"@\" or tostring(InitiatedBy.app.displayName) has \"@\"\n| mv-apply TargetResource = TargetResources on \n  (\n      where TargetResource.type =~ \"ServicePrincipal\" and array_length(TargetResource.modifiedProperties) > 0 and isnotnull(TargetResource.displayName)\n      | extend props = TargetResource.modifiedProperties,\n               Type = tostring(TargetResource.type),\n               PermissionsAddedTo = tostring(TargetResource.displayName)\n  )\n| mv-apply Property = props on \n  (\n      where Property.displayName =~ \"DelegatedPermissionGrant.Scope\"\n      | extend DisplayName = tostring(Property.displayName), Permissions = trim('\"',tostring(Property.newValue))\n  )\n| where Permissions has_any (\"Mail.Read\", \"Mail.ReadWrite\")\n| mv-apply AdditionalDetail = AdditionalDetails on \n  (\n      where AdditionalDetail.key =~ \"User-Agent\"\n      | extend InitiatingUserAgent = tostring(AdditionalDetail.value)\n  )\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| project-away props, TargetResource, AdditionalDetail, Property\n| join kind=leftouter(\n  AuditLogs\n  | where ActivityDisplayName has \"Consent to application\"\n  | mv-apply TargetResource = TargetResources on \n      (\n          where TargetResource.type =~ \"ServicePrincipal\"\n          | extend AppName = tostring(TargetResource.displayName),\n                   AppId = tostring(TargetResource.id)\n      )\n| project AppName, AppId, CorrelationId) on CorrelationId\n| project-away CorrelationId1\n| project-reorder TimeGenerated, OperationName, InitiatingUserPrincipalName, InitiatingAadUserId, InitiatingAppName, InitiatingAppServicePrincipalId, InitiatingIpAddress, InitiatingUserAgent, PermissionsAddedTo, Permissions, AppName, AppId, CorrelationId\n| extend Name = tostring(split(InitiatingUserPrincipalName,'@',0)[0]), UPNSuffix = tostring(split(InitiatingUserPrincipalName,'@',1)[0])\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Persistence"
        ],
        "tags": [
          "Solorigate",
          "NOBELIUM"
        ],
        "techniques": [
          "T1098"
        ],
        "templateVersion": "1.0.4",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}