Creation of expensive computes in Azure

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Id	9736e5f1-7b6e-4bfb-a708-e53ff1d182c3
Rulename	Creation of expensive computes in Azure
Description	Identifies the creation of large size or expensive VMs (with GPUs or with a large number of virtual CPUs) in Azure. An adversary may create new or update existing virtual machines to evade defenses or use them for cryptomining purposes. For Windows/Linux Vm Sizes, see https://docs.microsoft.com/azure/virtual-machines/windows/sizes Azure VM Naming Conventions, see https://docs.microsoft.com/azure/virtual-machines/vm-naming-conventions
Severity	Low
Tactics	DefenseEvasion
Techniques	T1578
Required data connectors	AzureActivity
Kind	Scheduled
Query frequency	1d
Query period	1d
Trigger threshold	1
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/Creation_of_Expensive_Computes_in_Azure.yaml
Version	2.0.1
Arm template	9736e5f1-7b6e-4bfb-a708-e53ff1d182c3.json

KQL

let tokens = dynamic(["416","208","192","128","120","96","80","72","64","48","44","40","g5","gs5","g4","gs4","nc12","nc24","nv24"]);
let operationList = dynamic(["microsoft.compute/virtualmachines/write", "microsoft.resources/deployments/write"]);
AzureActivity
| where OperationNameValue in~ (operationList)
| where ActivityStatusValue startswith "Accept"
| where Properties has 'vmSize'
| extend parsed_property= parse_json(tostring((parse_json(Properties).responseBody))).properties
| extend vmSize = tostring((parsed_property.hardwareProfile).vmSize)
| where vmSize has_any (tokens)
| extend ComputerName = tostring((parsed_property.osProfile).computerName)
| project TimeGenerated, OperationNameValue, ActivityStatusValue, Caller, CallerIpAddress, ComputerName, vmSize
| extend Name = tostring(split(Caller,'@',0)[0]), UPNSuffix = tostring(split(Caller,'@',1)[0])

YAML

severity: Low
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/Creation_of_Expensive_Computes_in_Azure.yaml
description: |
  'Identifies the creation of large size or expensive VMs (with GPUs or with a large number of virtual CPUs) in Azure.
  An adversary may create new or update existing virtual machines to evade defenses or use them for cryptomining purposes.
  For Windows/Linux Vm Sizes, see https://docs.microsoft.com/azure/virtual-machines/windows/sizes 
  Azure VM Naming Conventions, see https://docs.microsoft.com/azure/virtual-machines/vm-naming-conventions'  
triggerOperator: gt
queryPeriod: 1d
requiredDataConnectors:
- dataTypes:
  - AzureActivity
  connectorId: AzureActivity
queryFrequency: 1d
triggerThreshold: 1
tactics:
- DefenseEvasion
query: |
  let tokens = dynamic(["416","208","192","128","120","96","80","72","64","48","44","40","g5","gs5","g4","gs4","nc12","nc24","nv24"]);
  let operationList = dynamic(["microsoft.compute/virtualmachines/write", "microsoft.resources/deployments/write"]);
  AzureActivity
  | where OperationNameValue in~ (operationList)
  | where ActivityStatusValue startswith "Accept"
  | where Properties has 'vmSize'
  | extend parsed_property= parse_json(tostring((parse_json(Properties).responseBody))).properties
  | extend vmSize = tostring((parsed_property.hardwareProfile).vmSize)
  | where vmSize has_any (tokens)
  | extend ComputerName = tostring((parsed_property.osProfile).computerName)
  | project TimeGenerated, OperationNameValue, ActivityStatusValue, Caller, CallerIpAddress, ComputerName, vmSize
  | extend Name = tostring(split(Caller,'@',0)[0]), UPNSuffix = tostring(split(Caller,'@',1)[0])  
status: Available
kind: Scheduled
relevantTechniques:
- T1578
version: 2.0.1
id: 9736e5f1-7b6e-4bfb-a708-e53ff1d182c3
entityMappings:
- fieldMappings:
  - columnName: Name
    identifier: Name
  - columnName: UPNSuffix
    identifier: UPNSuffix
  entityType: Account
- fieldMappings:
  - columnName: CallerIpAddress
    identifier: Address
  entityType: IP
name: Creation of expensive computes in Azure

ARM

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/9736e5f1-7b6e-4bfb-a708-e53ff1d182c3')]",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/9736e5f1-7b6e-4bfb-a708-e53ff1d182c3')]",
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules",
      "kind": "Scheduled",
      "apiVersion": "2022-11-01-preview",
      "properties": {
        "displayName": "Creation of expensive computes in Azure",
        "description": "'Identifies the creation of large size or expensive VMs (with GPUs or with a large number of virtual CPUs) in Azure.\nAn adversary may create new or update existing virtual machines to evade defenses or use them for cryptomining purposes.\nFor Windows/Linux Vm Sizes, see https://docs.microsoft.com/azure/virtual-machines/windows/sizes \nAzure VM Naming Conventions, see https://docs.microsoft.com/azure/virtual-machines/vm-naming-conventions'\n",
        "severity": "Low",
        "enabled": true,
        "query": "let tokens = dynamic([\"416\",\"208\",\"192\",\"128\",\"120\",\"96\",\"80\",\"72\",\"64\",\"48\",\"44\",\"40\",\"g5\",\"gs5\",\"g4\",\"gs4\",\"nc12\",\"nc24\",\"nv24\"]);\nlet operationList = dynamic([\"microsoft.compute/virtualmachines/write\", \"microsoft.resources/deployments/write\"]);\nAzureActivity\n| where OperationNameValue in~ (operationList)\n| where ActivityStatusValue startswith \"Accept\"\n| where Properties has 'vmSize'\n| extend parsed_property= parse_json(tostring((parse_json(Properties).responseBody))).properties\n| extend vmSize = tostring((parsed_property.hardwareProfile).vmSize)\n| where vmSize has_any (tokens)\n| extend ComputerName = tostring((parsed_property.osProfile).computerName)\n| project TimeGenerated, OperationNameValue, ActivityStatusValue, Caller, CallerIpAddress, ComputerName, vmSize\n| extend Name = tostring(split(Caller,'@',0)[0]), UPNSuffix = tostring(split(Caller,'@',1)[0])\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 1,
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "techniques": [
          "T1578"
        ],
        "alertRuleTemplateName": "9736e5f1-7b6e-4bfb-a708-e53ff1d182c3",
        "customDetails": null,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "Name",
                "identifier": "Name"
              },
              {
                "columnName": "UPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "CallerIpAddress",
                "identifier": "Address"
              }
            ]
          }
        ],
        "status": "Available",
        "templateVersion": "2.0.1",
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/Creation_of_Expensive_Computes_in_Azure.yaml"
      }
    }
  ]
}