Back
Id54e22fed-0ec6-4fb2-8312-2a3809a93f63
Rulenamefull_access_as_app Granted To Application
DescriptionThis detection looks for the full_access_as_app permission being granted to an OAuth application with Admin Consent.

This permission provide access to all Exchange mailboxes via the EWS API can could be exploited to access sensitive data by being added to a compromised application. The application granted this permission should be reviewed to ensure that it is absolutely necessary for the applications function.

Ref: https://learn.microsoft.com/graph/auth-limit-mailbox-access
SeverityMedium
TacticsDefenseEvasion
TechniquesT1550.001
Required data connectorsAzureActiveDirectory
KindScheduled
Query frequency1h
Query period1h
Trigger threshold0
Trigger operatorgt
Source Urihttps://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft%20Entra%20ID/Analytic%20Rules/ExchangeFullAccessGrantedToApp.yaml
Version1.0.2
Arm template54e22fed-0ec6-4fb2-8312-2a3809a93f63.json
Deploy To Azure
AuditLogs
| where LoggedByService =~ "Core Directory"
| where Category =~ "ApplicationManagement"
| where OperationName =~ "Consent to application"
| where TargetResources has "full_access_as_app"
| mv-expand TargetResources
| extend OAuthAppName = TargetResources.displayName
| extend ModifiedProperties = TargetResources.modifiedProperties 
| mv-apply Property = ModifiedProperties on 
  (
      where Property.displayName =~ "ConsentContext.isAdminConsent"
      | extend AdminConsent = tostring(Property.newValue)
  )
| mv-apply Property = ModifiedProperties on 
  (
      where Property.displayName =~ "ConsentAction.Permissions"
      | extend Permissions = tostring(Property.newValue)
  )
| mv-apply Property = ModifiedProperties on 
  (
      where Property.displayName =~ "TargetId.ServicePrincipalNames"
      | extend AppId = tostring(Property.newValue)
  )
| mv-apply Property = AdditionalDetails on 
  (
      where Property.key =~ "User-Agent"
      | extend InitiatingUserAgent = replace('"', '', tostring(Property.value))
  )
| project-away Property
| parse Permissions with * "ConsentType: " GrantConsentType ", Scope: " GrantScope1 "," *
| where GrantScope1 =~ "full_access_as_app"
| 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-reorder TimeGenerated, OAuthAppName, AppId, AdminConsent, Permissions, InitiatingUserPrincipalName, InitiatingAadUserId, InitiatingAppName, InitiatingAppServicePrincipalId, InitiatingIpAddress, InitiatingUserAgent, GrantScope1, GrantConsentType
| extend GrantInitiatedBy = tostring(iff(isnotempty(InitiatingUserPrincipalName), InitiatingUserPrincipalName, InitiatingAppName))
| extend Name = split(InitiatingUserPrincipalName, "@")[0], UPNSuffix = split(InitiatingUserPrincipalName, "@")[1]
version: 1.0.2
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft%20Entra%20ID/Analytic%20Rules/ExchangeFullAccessGrantedToApp.yaml
triggerThreshold: 0
requiredDataConnectors:
- dataTypes:
  - AuditLogs
  connectorId: AzureActiveDirectory
tactics:
- DefenseEvasion
relevantTechniques:
- T1550.001
kind: Scheduled
alertDetailsOverride:
  alertDescriptionFormat: |
    This detection looks for the full_access_as_app permission being granted to an OAuth application with Admin Consent.
    This permission provide access to all Exchange mailboxes via the EWS API can could be exploited to access sensitive data 
    by being added to a compromised application. The application granted this permission should be reviewed to ensure that it 
    is absolutely necessary for the applications function.
    In this case {{GrantInitiatedBy}} granted full_access_as_app to {{OAuthAppName}} from {{InitiatingIpAddress}}
    Ref: https://learn.microsoft.com/graph/auth-limit-mailbox-access
  alertDisplayNameFormat: User or App {{GrantInitiatedBy}} granted full_access_as_app to {{OAuthAppName}}
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: InitiatingUserPrincipalName
  - identifier: Name
    columnName: Name
  - identifier: UPNSuffix
    columnName: UPNSuffix
  entityType: Account
- fieldMappings:
  - identifier: AadUserId
    columnName: InitiatingAadUserId
  entityType: Account
- fieldMappings:
  - identifier: AadUserId
    columnName: InitiatingAppServicePrincipalId
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: InitiatingIpAddress
  entityType: IP
description: |
  'This detection looks for the full_access_as_app permission being granted to an OAuth application with Admin Consent.
  This permission provide access to all Exchange mailboxes via the EWS API can could be exploited to access sensitive data by being added to a compromised application. The application granted this permission should be reviewed to ensure that it is absolutely necessary for the applications function.
  Ref: https://learn.microsoft.com/graph/auth-limit-mailbox-access'
triggerOperator: gt
status: Available
queryFrequency: 1h
id: 54e22fed-0ec6-4fb2-8312-2a3809a93f63
name: full_access_as_app Granted To Application
severity: Medium
query: |
  AuditLogs
  | where LoggedByService =~ "Core Directory"
  | where Category =~ "ApplicationManagement"
  | where OperationName =~ "Consent to application"
  | where TargetResources has "full_access_as_app"
  | mv-expand TargetResources
  | extend OAuthAppName = TargetResources.displayName
  | extend ModifiedProperties = TargetResources.modifiedProperties 
  | mv-apply Property = ModifiedProperties on 
    (
        where Property.displayName =~ "ConsentContext.isAdminConsent"
        | extend AdminConsent = tostring(Property.newValue)
    )
  | mv-apply Property = ModifiedProperties on 
    (
        where Property.displayName =~ "ConsentAction.Permissions"
        | extend Permissions = tostring(Property.newValue)
    )
  | mv-apply Property = ModifiedProperties on 
    (
        where Property.displayName =~ "TargetId.ServicePrincipalNames"
        | extend AppId = tostring(Property.newValue)
    )
  | mv-apply Property = AdditionalDetails on 
    (
        where Property.key =~ "User-Agent"
        | extend InitiatingUserAgent = replace('"', '', tostring(Property.value))
    )
  | project-away Property
  | parse Permissions with * "ConsentType: " GrantConsentType ", Scope: " GrantScope1 "," *
  | where GrantScope1 =~ "full_access_as_app"
  | 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-reorder TimeGenerated, OAuthAppName, AppId, AdminConsent, Permissions, InitiatingUserPrincipalName, InitiatingAadUserId, InitiatingAppName, InitiatingAppServicePrincipalId, InitiatingIpAddress, InitiatingUserAgent, GrantScope1, GrantConsentType
  | extend GrantInitiatedBy = tostring(iff(isnotempty(InitiatingUserPrincipalName), InitiatingUserPrincipalName, InitiatingAppName))
  | extend Name = split(InitiatingUserPrincipalName, "@")[0], UPNSuffix = split(InitiatingUserPrincipalName, "@")[1]
queryPeriod: 1h
customDetails:
  OAuthApplication: OAuthAppName
  UserAgent: InitiatingUserAgent
  OAuthAppId: AppId
{
  "$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/54e22fed-0ec6-4fb2-8312-2a3809a93f63')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/54e22fed-0ec6-4fb2-8312-2a3809a93f63')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "This detection looks for the full_access_as_app permission being granted to an OAuth application with Admin Consent.\nThis permission provide access to all Exchange mailboxes via the EWS API can could be exploited to access sensitive data \nby being added to a compromised application. The application granted this permission should be reviewed to ensure that it \nis absolutely necessary for the applications function.\nIn this case {{GrantInitiatedBy}} granted full_access_as_app to {{OAuthAppName}} from {{InitiatingIpAddress}}\nRef: https://learn.microsoft.com/graph/auth-limit-mailbox-access\n",
          "alertDisplayNameFormat": "User or App {{GrantInitiatedBy}} granted full_access_as_app to {{OAuthAppName}}"
        },
        "alertRuleTemplateName": "54e22fed-0ec6-4fb2-8312-2a3809a93f63",
        "customDetails": {
          "OAuthAppId": "AppId",
          "OAuthApplication": "OAuthAppName",
          "UserAgent": "InitiatingUserAgent"
        },
        "description": "'This detection looks for the full_access_as_app permission being granted to an OAuth application with Admin Consent.\nThis permission provide access to all Exchange mailboxes via the EWS API can could be exploited to access sensitive data by being added to a compromised application. The application granted this permission should be reviewed to ensure that it is absolutely necessary for the applications function.\nRef: https://learn.microsoft.com/graph/auth-limit-mailbox-access'\n",
        "displayName": "full_access_as_app 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%20Entra%20ID/Analytic%20Rules/ExchangeFullAccessGrantedToApp.yaml",
        "query": "AuditLogs\n| where LoggedByService =~ \"Core Directory\"\n| where Category =~ \"ApplicationManagement\"\n| where OperationName =~ \"Consent to application\"\n| where TargetResources has \"full_access_as_app\"\n| mv-expand TargetResources\n| extend OAuthAppName = TargetResources.displayName\n| extend ModifiedProperties = TargetResources.modifiedProperties \n| mv-apply Property = ModifiedProperties on \n  (\n      where Property.displayName =~ \"ConsentContext.isAdminConsent\"\n      | extend AdminConsent = tostring(Property.newValue)\n  )\n| mv-apply Property = ModifiedProperties on \n  (\n      where Property.displayName =~ \"ConsentAction.Permissions\"\n      | extend Permissions = tostring(Property.newValue)\n  )\n| mv-apply Property = ModifiedProperties on \n  (\n      where Property.displayName =~ \"TargetId.ServicePrincipalNames\"\n      | extend AppId = tostring(Property.newValue)\n  )\n| mv-apply Property = AdditionalDetails on \n  (\n      where Property.key =~ \"User-Agent\"\n      | extend InitiatingUserAgent = replace('\"', '', tostring(Property.value))\n  )\n| project-away Property\n| parse Permissions with * \"ConsentType: \" GrantConsentType \", Scope: \" GrantScope1 \",\" *\n| where GrantScope1 =~ \"full_access_as_app\"\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-reorder TimeGenerated, OAuthAppName, AppId, AdminConsent, Permissions, InitiatingUserPrincipalName, InitiatingAadUserId, InitiatingAppName, InitiatingAppServicePrincipalId, InitiatingIpAddress, InitiatingUserAgent, GrantScope1, GrantConsentType\n| extend GrantInitiatedBy = tostring(iff(isnotempty(InitiatingUserPrincipalName), InitiatingUserPrincipalName, InitiatingAppName))\n| extend Name = split(InitiatingUserPrincipalName, \"@\")[0], UPNSuffix = split(InitiatingUserPrincipalName, \"@\")[1]\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [
          "T1550.001"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "techniques": [
          "T1550"
        ],
        "templateVersion": "1.0.2",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}