Explicit MFA Deny

let aadFunc = (tableName: string) {
    table(tableName)
    | where ResultType == 500121
    | where Status has "MFA Denied; user declined the authentication" or Status has "MFA denied; Phone App Reported Fraud"
    | extend Type = Type, PublicIP = IPAddress
    | extend
        Name = tostring(split(UserPrincipalName, '@', 0)[0]),
        UPNSuffix = tostring(split(UserPrincipalName, '@', 1)[0])
};
let aadSignin = aadFunc("SigninLogs");
let dvcInfo = DeviceInfo
    | extend SensorHealthState = column_ifexists("SensorHealthState", "")
    | where OnboardingStatus == "Onboarded" and SensorHealthState == "Active"
    | project PublicIP, AadDeviceId;
let aadNonInt = aadFunc("AADNonInteractiveUserSignInLogs");
union isfuzzy=true aadSignin, aadNonInt
| join kind=leftouter dvcInfo on PublicIP

relevantTechniques:
- T1110
queryPeriod: 1h
tactics:
- CredentialAccess
requiredDataConnectors:
- dataTypes:
  - SigninLogs
  connectorId: AzureActiveDirectory
- dataTypes:
  - AADNonInteractiveUserSignInLogs
  connectorId: AzureActiveDirectory
- dataTypes:
  - DeviceInfo
  connectorId: MicrosoftThreatProtection
triggerThreshold: 0
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: UserPrincipalName
  - identifier: Name
    columnName: Name
  - identifier: UPNSuffix
    columnName: UPNSuffix
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: PublicIP
  entityType: IP
- fieldMappings:
  - identifier: ResourceId
    columnName: ResourceId
  entityType: AzureResource
- fieldMappings:
  - identifier: Name
    columnName: AppDisplayName
  - identifier: AppId
    columnName: AppId
  entityType: CloudApplication
name: Explicit MFA Deny
status: Available
query: |
  let aadFunc = (tableName: string) {
      table(tableName)
      | where ResultType == 500121
      | where Status has "MFA Denied; user declined the authentication" or Status has "MFA denied; Phone App Reported Fraud"
      | extend Type = Type, PublicIP = IPAddress
      | extend
          Name = tostring(split(UserPrincipalName, '@', 0)[0]),
          UPNSuffix = tostring(split(UserPrincipalName, '@', 1)[0])
  };
  let aadSignin = aadFunc("SigninLogs");
  let dvcInfo = DeviceInfo
      | extend SensorHealthState = column_ifexists("SensorHealthState", "")
      | where OnboardingStatus == "Onboarded" and SensorHealthState == "Active"
      | project PublicIP, AadDeviceId;
  let aadNonInt = aadFunc("AADNonInteractiveUserSignInLogs");
  union isfuzzy=true aadSignin, aadNonInt
  | join kind=leftouter dvcInfo on PublicIP  
queryFrequency: 1h
id: a22740ec-fc1e-4c91-8de6-c29c6450ad00
severity: Medium
description: |
    'User explicitly denies MFA push, indicating that login was not expected and the account's password may be compromised.'
version: 1.0.6
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Entra ID/Analytic Rules/ExplicitMFADeny.yaml
kind: Scheduled
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": "2023-02-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/a22740ec-fc1e-4c91-8de6-c29c6450ad00')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/a22740ec-fc1e-4c91-8de6-c29c6450ad00')]",
      "properties": {
        "alertRuleTemplateName": "a22740ec-fc1e-4c91-8de6-c29c6450ad00",
        "customDetails": null,
        "description": "'User explicitly denies MFA push, indicating that login was not expected and the account's password may be compromised.'\n",
        "displayName": "Explicit MFA Deny",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "UserPrincipalName",
                "identifier": "FullName"
              },
              {
                "columnName": "Name",
                "identifier": "Name"
              },
              {
                "columnName": "UPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "PublicIP",
                "identifier": "Address"
              }
            ]
          },
          {
            "entityType": "AzureResource",
            "fieldMappings": [
              {
                "columnName": "ResourceId",
                "identifier": "ResourceId"
              }
            ]
          },
          {
            "entityType": "CloudApplication",
            "fieldMappings": [
              {
                "columnName": "AppDisplayName",
                "identifier": "Name"
              },
              {
                "columnName": "AppId",
                "identifier": "AppId"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Entra ID/Analytic Rules/ExplicitMFADeny.yaml",
        "query": "let aadFunc = (tableName: string) {\n    table(tableName)\n    | where ResultType == 500121\n    | where Status has \"MFA Denied; user declined the authentication\" or Status has \"MFA denied; Phone App Reported Fraud\"\n    | extend Type = Type, PublicIP = IPAddress\n    | extend\n        Name = tostring(split(UserPrincipalName, '@', 0)[0]),\n        UPNSuffix = tostring(split(UserPrincipalName, '@', 1)[0])\n};\nlet aadSignin = aadFunc(\"SigninLogs\");\nlet dvcInfo = DeviceInfo\n    | extend SensorHealthState = column_ifexists(\"SensorHealthState\", \"\")\n    | where OnboardingStatus == \"Onboarded\" and SensorHealthState == \"Active\"\n    | project PublicIP, AadDeviceId;\nlet aadNonInt = aadFunc(\"AADNonInteractiveUserSignInLogs\");\nunion isfuzzy=true aadSignin, aadNonInt\n| join kind=leftouter dvcInfo on PublicIP\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "CredentialAccess"
        ],
        "techniques": [
          "T1110"
        ],
        "templateVersion": "1.0.6",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}