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])

version: 1.0.6
tactics:
- DefenseEvasion
name: Privileged User Logon from new ASN
queryPeriod: 7d
triggerThreshold: 0
entityMappings:
- fieldMappings:
  - columnName: UserPrincipalName
    identifier: FullName
  - columnName: AccountName
    identifier: Name
  - columnName: AccountUPNSuffix
    identifier: UPNSuffix
  entityType: Account
- fieldMappings:
  - columnName: IPAddress
    identifier: Address
  entityType: IP
triggerOperator: gt
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/SigninLogs/PrivilegedUserLogonfromnewASN.yaml
requiredDataConnectors:
- connectorId: AzureActiveDirectory
  dataTypes:
  - SigninLogs
- connectorId: BehaviorAnalytics
  dataTypes:
  - BehaviorAnalytics
- connectorId: BehaviorAnalytics
  dataTypes:
  - IdentityInfo
id: 55073036-bb86-47d3-a85a-b113ac3d9396
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])  
metadata:
  author:
    name: Microsoft Security Research
  support:
    tier: Community
  source:
    kind: Community
  categories:
    domains:
    - Identity
    - Security - Others
relevantTechniques:
- T1078.004
severity: Medium
queryFrequency: 1d
kind: Scheduled
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.'  
tags:
- AADSecOpsGuide

{
  "$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"
    }
  ]
}