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/expensive VMs (GPU or with large no of virtual CPUs) in Azure. Adversary may create new or update existing virtual machines sizes to evade defenses or use it for cryptomining purposes. For Windows/Linux Vm Sizes - https://docs.microsoft.com/azure/virtual-machines/windows/sizes Azure VM Naming Conventions - 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	2.0.0
Arm template	9736e5f1-7b6e-4bfb-a708-e53ff1d182c3.json

KQL

let tokens = dynamic(["416","208","128","120","96","80","72","64","48","44","40","g5","gs5","g4","gs4","nc12","nc24","nv12"]);
let operationList = dynamic(["microsoft.compute/virtualmachines/write", "microsoft.resources/deployments/write"]);
AzureActivity
| where tolower(OperationNameValue) in (operationList)
| where ActivityStatusValue == "Accepted" 
| where isnotempty(Properties)
| extend vmSize = tolower(tostring(parse_json(tostring(parse_json(tostring(parse_json(tostring(parse_json(Properties).responseBody)).properties)).hardwareProfile)).vmSize))
| where isnotempty(vmSize)
| where vmSize has_any (tokens) 
| extend ComputerName = tostring(parse_json(tostring(parse_json(tostring(parse_json(tostring(parse_json(Properties).responseBody)).properties)).osProfile)).computerName)
| extend clientIpAddress = tostring(parse_json(HTTPRequest).clientIpAddress)
| project TimeGenerated, OperationNameValue, ActivityStatusValue, Caller, CallerIpAddress, ComputerName, vmSize
| extend timestamp = TimeGenerated, AccountCustomEntity = Caller, IPCustomEntity = CallerIpAddress

YAML

queryFrequency: 1d
triggerOperator: gt
tactics:
- DefenseEvasion
description: |
  'Identifies the creation of large size/expensive VMs (GPU or with large no of virtual CPUs) in Azure.
  Adversary may create new or update existing virtual machines sizes to evade defenses 
  or use it for cryptomining purposes.
  For Windows/Linux Vm Sizes - https://docs.microsoft.com/azure/virtual-machines/windows/sizes 
  Azure VM Naming Conventions - https://docs.microsoft.com/azure/virtual-machines/vm-naming-conventions'  
status: Available
relevantTechniques:
- T1578
name: Creation of expensive computes in Azure
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/Creation_of_Expensive_Computes_in_Azure.yaml
severity: Low
triggerThreshold: 1
version: 2.0.0
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: FullName
    columnName: AccountCustomEntity
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: IPCustomEntity
query: |
  let tokens = dynamic(["416","208","128","120","96","80","72","64","48","44","40","g5","gs5","g4","gs4","nc12","nc24","nv12"]);
  let operationList = dynamic(["microsoft.compute/virtualmachines/write", "microsoft.resources/deployments/write"]);
  AzureActivity
  | where tolower(OperationNameValue) in (operationList)
  | where ActivityStatusValue == "Accepted" 
  | where isnotempty(Properties)
  | extend vmSize = tolower(tostring(parse_json(tostring(parse_json(tostring(parse_json(tostring(parse_json(Properties).responseBody)).properties)).hardwareProfile)).vmSize))
  | where isnotempty(vmSize)
  | where vmSize has_any (tokens) 
  | extend ComputerName = tostring(parse_json(tostring(parse_json(tostring(parse_json(tostring(parse_json(Properties).responseBody)).properties)).osProfile)).computerName)
  | extend clientIpAddress = tostring(parse_json(HTTPRequest).clientIpAddress)
  | project TimeGenerated, OperationNameValue, ActivityStatusValue, Caller, CallerIpAddress, ComputerName, vmSize
  | extend timestamp = TimeGenerated, AccountCustomEntity = Caller, IPCustomEntity = CallerIpAddress  
id: 9736e5f1-7b6e-4bfb-a708-e53ff1d182c3
requiredDataConnectors:
- connectorId: AzureActivity
  dataTypes:
  - AzureActivity
kind: Scheduled
queryPeriod: 1d

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",
      "properties": {
        "displayName": "Creation of expensive computes in Azure",
        "description": "'Identifies the creation of large size/expensive VMs (GPU or with large no of virtual CPUs) in Azure.\nAdversary may create new or update existing virtual machines sizes to evade defenses \nor use it for cryptomining purposes.\nFor Windows/Linux Vm Sizes - https://docs.microsoft.com/azure/virtual-machines/windows/sizes \nAzure VM Naming Conventions - https://docs.microsoft.com/azure/virtual-machines/vm-naming-conventions'\n",
        "severity": "Low",
        "enabled": true,
        "query": "let tokens = dynamic([\"416\",\"208\",\"128\",\"120\",\"96\",\"80\",\"72\",\"64\",\"48\",\"44\",\"40\",\"g5\",\"gs5\",\"g4\",\"gs4\",\"nc12\",\"nc24\",\"nv12\"]);\nlet operationList = dynamic([\"microsoft.compute/virtualmachines/write\", \"microsoft.resources/deployments/write\"]);\nAzureActivity\n| where tolower(OperationNameValue) in (operationList)\n| where ActivityStatusValue == \"Accepted\" \n| where isnotempty(Properties)\n| extend vmSize = tolower(tostring(parse_json(tostring(parse_json(tostring(parse_json(tostring(parse_json(Properties).responseBody)).properties)).hardwareProfile)).vmSize))\n| where isnotempty(vmSize)\n| where vmSize has_any (tokens) \n| extend ComputerName = tostring(parse_json(tostring(parse_json(tostring(parse_json(tostring(parse_json(Properties).responseBody)).properties)).osProfile)).computerName)\n| extend clientIpAddress = tostring(parse_json(HTTPRequest).clientIpAddress)\n| project TimeGenerated, OperationNameValue, ActivityStatusValue, Caller, CallerIpAddress, ComputerName, vmSize\n| extend timestamp = TimeGenerated, AccountCustomEntity = Caller, IPCustomEntity = CallerIpAddress\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": [
              {
                "identifier": "FullName",
                "columnName": "AccountCustomEntity"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "identifier": "Address",
                "columnName": "IPCustomEntity"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/Creation_of_Expensive_Computes_in_Azure.yaml",
        "status": "Available",
        "templateVersion": "2.0.0"
      }
    }
  ]
}