Anomolous Single Factor Signin

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Id	f7c3f5c8-71ea-49ff-b8b3-148f0e346291
Rulename	Anomolous Single Factor Signin
Description	Detects successful signins using single factor authentication where the device, location, and ASN are abnormal. Single factor authentications pose an opportunity to access compromised accounts, investigate these for anomalous occurrencess. Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-devices#non-compliant-device-sign-in
Severity	Low
Tactics	InitialAccess
Techniques	T1078.004
Required data connectors	AzureActiveDirectory
Kind	Scheduled
Query frequency	1d
Query period	7d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Detections/SigninLogs/AnomolousSingleFactorSignin.yaml
Version	1.0.3
Arm template	f7c3f5c8-71ea-49ff-b8b3-148f0e346291.json

KQL

let known_locations = (SigninLogs
  | where TimeGenerated between(ago(7d)..ago(1d))
  | where ResultType == 0
  | extend LocationDetail = strcat(Location, "-", LocationDetails.state)
  | summarize by LocationDetail);
  let known_asn = (SigninLogs
  | where TimeGenerated between(ago(7d)..ago(1d))
  | where ResultType == 0
  | summarize by AutonomousSystemNumber);
  SigninLogs
  | where TimeGenerated > ago(1d)
  | where ResultType == 0
  | where isempty(DeviceDetail.deviceId)
  | where AuthenticationRequirement == "singleFactorAuthentication"
  | extend LocationDetail = strcat(Location, "-", LocationDetails.state)
  | where AutonomousSystemNumber !in (known_asn) and LocationDetail !in (known_locations)

YAML

relevantTechniques:
- T1078.004
queryPeriod: 7d
tactics:
- InitialAccess
requiredDataConnectors:
- dataTypes:
  - SigninLogs
  connectorId: AzureActiveDirectory
triggerThreshold: 0
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: UserPrincipalName
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: IPAddress
  entityType: IP
name: Anomolous Single Factor Signin
tags:
- AADSecOpsGuide
query: |
  let known_locations = (SigninLogs
    | where TimeGenerated between(ago(7d)..ago(1d))
    | where ResultType == 0
    | extend LocationDetail = strcat(Location, "-", LocationDetails.state)
    | summarize by LocationDetail);
    let known_asn = (SigninLogs
    | where TimeGenerated between(ago(7d)..ago(1d))
    | where ResultType == 0
    | summarize by AutonomousSystemNumber);
    SigninLogs
    | where TimeGenerated > ago(1d)
    | where ResultType == 0
    | where isempty(DeviceDetail.deviceId)
    | where AuthenticationRequirement == "singleFactorAuthentication"
    | extend LocationDetail = strcat(Location, "-", LocationDetails.state)
    | where AutonomousSystemNumber !in (known_asn) and LocationDetail !in (known_locations)  
queryFrequency: 1d
id: f7c3f5c8-71ea-49ff-b8b3-148f0e346291
severity: Low
description: |
  'Detects successful signins using single factor authentication where the device, location, and ASN are abnormal.
    Single factor authentications pose an opportunity to access compromised accounts, investigate these for anomalous occurrencess.
    Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-devices#non-compliant-device-sign-in'  
metadata:
  source:
    kind: Community
  categories:
    domains:
    - Security - Others
  support:
    tier: Community
  author:
    name: Pete Bryan
version: 1.0.3
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/SigninLogs/AnomolousSingleFactorSignin.yaml
kind: Scheduled
triggerOperator: gt

ARM

{
  "$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/f7c3f5c8-71ea-49ff-b8b3-148f0e346291')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/f7c3f5c8-71ea-49ff-b8b3-148f0e346291')]",
      "properties": {
        "alertRuleTemplateName": "f7c3f5c8-71ea-49ff-b8b3-148f0e346291",
        "customDetails": null,
        "description": "'Detects successful signins using single factor authentication where the device, location, and ASN are abnormal.\n  Single factor authentications pose an opportunity to access compromised accounts, investigate these for anomalous occurrencess.\n  Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-devices#non-compliant-device-sign-in'\n",
        "displayName": "Anomolous Single Factor Signin",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "UserPrincipalName",
                "identifier": "FullName"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "IPAddress",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/SigninLogs/AnomolousSingleFactorSignin.yaml",
        "query": "let known_locations = (SigninLogs\n  | where TimeGenerated between(ago(7d)..ago(1d))\n  | where ResultType == 0\n  | extend LocationDetail = strcat(Location, \"-\", LocationDetails.state)\n  | summarize by LocationDetail);\n  let known_asn = (SigninLogs\n  | where TimeGenerated between(ago(7d)..ago(1d))\n  | where ResultType == 0\n  | summarize by AutonomousSystemNumber);\n  SigninLogs\n  | where TimeGenerated > ago(1d)\n  | where ResultType == 0\n  | where isempty(DeviceDetail.deviceId)\n  | where AuthenticationRequirement == \"singleFactorAuthentication\"\n  | extend LocationDetail = strcat(Location, \"-\", LocationDetails.state)\n  | where AutonomousSystemNumber !in (known_asn) and LocationDetail !in (known_locations)\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P7D",
        "severity": "Low",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "InitialAccess"
        ],
        "tags": [
          "AADSecOpsGuide"
        ],
        "techniques": [
          "T1078"
        ],
        "templateVersion": "1.0.3",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}