Trust Monitor Event

let timeframe = ago(5m);
DuoSecurityTrustMonitor_CL
| where TimeGenerated >= timeframe
| extend AccountName = tostring(split(surfaced_auth_user_name_s, "@")[0]), AccountUPNSuffix = tostring(split(surfaced_auth_user_name_s, "@")[1])

relevantTechniques:
- T1528
- T1555
name: Trust Monitor Event
requiredDataConnectors: []
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: surfaced_auth_user_name_s
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: surfaced_auth_access_device_ip_s
  entityType: IP
triggerThreshold: 0
id: 8dcf7238-a7d0-4cfd-8d0c-b230e3cd9182
tactics:
- CredentialAccess
version: 1.0.4
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/DuoSecurity/TrustMonitorEvent.yaml
queryPeriod: 5m
kind: Scheduled
metadata:
  categories:
    domains:
    - Security - Others
  author:
    name: SecurityJedi
  support:
    tier: Community
  source:
    kind: Community
queryFrequency: 5m
severity: Medium
description: |
    'This query identifies when a new trust monitor event is detected.'
query: |
  let timeframe = ago(5m);
  DuoSecurityTrustMonitor_CL
  | where TimeGenerated >= timeframe
  | extend AccountName = tostring(split(surfaced_auth_user_name_s, "@")[0]), AccountUPNSuffix = tostring(split(surfaced_auth_user_name_s, "@")[1])  
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/8dcf7238-a7d0-4cfd-8d0c-b230e3cd9182')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/8dcf7238-a7d0-4cfd-8d0c-b230e3cd9182')]",
      "properties": {
        "alertRuleTemplateName": "8dcf7238-a7d0-4cfd-8d0c-b230e3cd9182",
        "customDetails": null,
        "description": "'This query identifies when a new trust monitor event is detected.'\n",
        "displayName": "Trust Monitor Event",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "surfaced_auth_user_name_s",
                "identifier": "FullName"
              },
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountUPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "surfaced_auth_access_device_ip_s",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/DuoSecurity/TrustMonitorEvent.yaml",
        "query": "let timeframe = ago(5m);\nDuoSecurityTrustMonitor_CL\n| where TimeGenerated >= timeframe\n| extend AccountName = tostring(split(surfaced_auth_user_name_s, \"@\")[0]), AccountUPNSuffix = tostring(split(surfaced_auth_user_name_s, \"@\")[1])\n",
        "queryFrequency": "PT5M",
        "queryPeriod": "PT5M",
        "severity": "Medium",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "CredentialAccess"
        ],
        "techniques": [
          "T1528",
          "T1555"
        ],
        "templateVersion": "1.0.4",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}