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])

requiredDataConnectors:
- dataTypes:
  - SigninLogs
  connectorId: AzureActiveDirectory
- dataTypes:
  - BehaviorAnalytics
  connectorId: BehaviorAnalytics
- dataTypes:
  - IdentityInfo
  connectorId: BehaviorAnalytics
id: 55073036-bb86-47d3-a85a-b113ac3d9396
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/SigninLogs/PrivilegedUserLogonfromnewASN.yaml
triggerThreshold: 0
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])  
severity: Medium
entityMappings:
- fieldMappings:
  - columnName: UserPrincipalName
    identifier: FullName
  - columnName: AccountName
    identifier: Name
  - columnName: AccountUPNSuffix
    identifier: UPNSuffix
  entityType: Account
- fieldMappings:
  - columnName: IPAddress
    identifier: Address
  entityType: IP
tags:
- AADSecOpsGuide
tactics:
- DefenseEvasion
version: 1.0.6
kind: Scheduled
metadata:
  categories:
    domains:
    - Identity
    - Security - Others
  support:
    tier: Community
  author:
    name: Microsoft Security Research
  source:
    kind: Community
relevantTechniques:
- T1078.004
name: Privileged User Logon from new ASN
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.'  
queryPeriod: 7d

{
  "$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/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",
        "subTechniques": [
          "T1078.004"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "tags": [
          "AADSecOpsGuide"
        ],
        "techniques": [
          "T1078"
        ],
        "templateVersion": "1.0.6",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}