Privileged User Logon from new ASN

let admins=(IdentityInfo
  | where AssignedRoles contains "admin" or GroupMembership has "Admin"
  | summarize by tolower(AccountUPN));
  let known_asns = (
  SigninLogs
  | where TimeGenerated between(ago(14d)..ago(1d))
  | where ResultType == 0
  | summarize by AutonomousSystemNumber);
  SigninLogs
  | where TimeGenerated > ago(1d)
  | where ResultType == 0
  | where tolower(UserPrincipalName) in (admins)
  | where AutonomousSystemNumber !in (known_asns)
  | project-reorder TimeGenerated, UserPrincipalName, UserAgent, IPAddress, AutonomousSystemNumber
  | extend AccountName = tostring(split(UserPrincipalName, "@")[0]), AccountUPNSuffix = tostring(split(UserPrincipalName, "@")[1])

triggerOperator: gt
queryFrequency: 1d
description: |
  'Detects a successful logon by a privileged account from an ASN not logged in from in the last 14 days.
    Monitor these logons to ensure they are legitimate and identify if there are any similar sign ins.'  
version: 1.0.6
kind: Scheduled
triggerThreshold: 0
requiredDataConnectors:
- connectorId: AzureActiveDirectory
  dataTypes:
  - SigninLogs
- connectorId: BehaviorAnalytics
  dataTypes:
  - BehaviorAnalytics
- connectorId: BehaviorAnalytics
  dataTypes:
  - IdentityInfo
queryPeriod: 7d
name: Privileged User Logon from new ASN
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/SigninLogs/PrivilegedUserLogonfromnewASN.yaml
id: 55073036-bb86-47d3-a85a-b113ac3d9396
tags:
- AADSecOpsGuide
tactics:
- DefenseEvasion
metadata:
  source:
    kind: Community
  author:
    name: Microsoft Security Research
  categories:
    domains:
    - Identity
    - Security - Others
  support:
    tier: Community
relevantTechniques:
- T1078.004
severity: Medium
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: UserPrincipalName
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: IPAddress
  entityType: IP
query: |
  let admins=(IdentityInfo
    | where AssignedRoles contains "admin" or GroupMembership has "Admin"
    | summarize by tolower(AccountUPN));
    let known_asns = (
    SigninLogs
    | where TimeGenerated between(ago(14d)..ago(1d))
    | where ResultType == 0
    | summarize by AutonomousSystemNumber);
    SigninLogs
    | where TimeGenerated > ago(1d)
    | where ResultType == 0
    | where tolower(UserPrincipalName) in (admins)
    | where AutonomousSystemNumber !in (known_asns)
    | project-reorder TimeGenerated, UserPrincipalName, UserAgent, IPAddress, AutonomousSystemNumber
    | extend AccountName = tostring(split(UserPrincipalName, "@")[0]), AccountUPNSuffix = tostring(split(UserPrincipalName, "@")[1])  

{
  "$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/55073036-bb86-47d3-a85a-b113ac3d9396')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/55073036-bb86-47d3-a85a-b113ac3d9396')]",
      "properties": {
        "alertRuleTemplateName": "55073036-bb86-47d3-a85a-b113ac3d9396",
        "customDetails": null,
        "description": "'Detects a successful logon by a privileged account from an ASN not logged in from in the last 14 days.\n  Monitor these logons to ensure they are legitimate and identify if there are any similar sign ins.'\n",
        "displayName": "Privileged User Logon from new ASN",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "UserPrincipalName",
                "identifier": "FullName"
              },
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountUPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "IPAddress",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/SigninLogs/PrivilegedUserLogonfromnewASN.yaml",
        "query": "let admins=(IdentityInfo\n  | where AssignedRoles contains \"admin\" or GroupMembership has \"Admin\"\n  | summarize by tolower(AccountUPN));\n  let known_asns = (\n  SigninLogs\n  | where TimeGenerated between(ago(14d)..ago(1d))\n  | where ResultType == 0\n  | summarize by AutonomousSystemNumber);\n  SigninLogs\n  | where TimeGenerated > ago(1d)\n  | where ResultType == 0\n  | where tolower(UserPrincipalName) in (admins)\n  | where AutonomousSystemNumber !in (known_asns)\n  | project-reorder TimeGenerated, UserPrincipalName, UserAgent, IPAddress, AutonomousSystemNumber\n  | extend AccountName = tostring(split(UserPrincipalName, \"@\")[0]), AccountUPNSuffix = tostring(split(UserPrincipalName, \"@\")[1])\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P7D",
        "severity": "Medium",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "tags": [
          "AADSecOpsGuide"
        ],
        "techniques": [
          "T1078"
        ],
        "templateVersion": "1.0.6",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}