[Deprecated] - MSHTML vulnerability CVE-2021-40444 attack

( union isfuzzy=true
(SecurityEvent
| where EventID==4688
| where isnotempty(CommandLine)
| extend FileName = Process, ProcessCommandLine = CommandLine
| where (FileName in~('control.exe','rundll32.exe') and ProcessCommandLine has '.cpl:')
  or ProcessCommandLine matches regex @'\".[a-zA-Z]{2,4}:\.\.\/\.\.'
| extend timestamp = TimeGenerated, AccountCustomEntity = Account, HostCustomEntity = Computer
),
(DeviceProcessEvents
| where (FileName in~('control.exe','rundll32.exe') and ProcessCommandLine has '.cpl:')
or ProcessCommandLine matches regex @'\".[a-zA-Z]{2,4}:\.\.\/\.\.'
| extend timestamp = TimeGenerated, AccountCustomEntity = InitiatingProcessAccountUpn, HostCustomEntity = DeviceName
),
(Event
| where Source == "Microsoft-Windows-Sysmon"
| where EventID == 1 
| extend EventData = parse_xml(EventData).DataItem.EventData.Data
| mv-expand bagexpansion=array EventData
| evaluate bag_unpack(EventData)
| extend Key = tostring(column_ifexists('@Name', "")), Value = column_ifexists('#text', "")
| evaluate pivot(Key, any(Value), TimeGenerated, Source, EventLog, Computer, EventLevel, EventLevelName, UserName, RenderedDescription, MG, ManagementGroupName, Type, _ResourceId)
| extend Image = column_ifexists("Image", ""), ProcessCommandLine = column_ifexists("CommandLine", "")
| extend FileName = split(Image, '\\', -1)[-1]
| where (FileName in~('control.exe','rundll32.exe') and ProcessCommandLine has '.cpl:')
  or ProcessCommandLine matches regex @'\".[a-zA-Z]{2,4}:\.\.\/\.\.'
| extend timestamp = TimeGenerated, AccountCustomEntity = UserName, HostCustomEntity = Computer
)
)

kind: Scheduled
entityMappings:
- entityType: Account
  fieldMappings:
  - columnName: AccountCustomEntity
    identifier: FullName
- entityType: Host
  fieldMappings:
  - columnName: HostCustomEntity
    identifier: FullName
description: |
    'This query has been deprecated as the associated IoCs (Indicators of Compromise) are outdated and no longer relevant. To ensure effective threat detection, it is recommended to implement Microsoft's Threat Intelligence solution, which enables matching your log data with the most up-to-date IoCs generated by Microsoft. This solution can be installed from the Microsoft Sentinel Content Hub if not currently deployed. More details on the Content Hub can be found here: https://learn.microsoft.com/azure/sentinel/sentinel-solutions-deploy'
severity: High
queryFrequency: 1h
triggerThreshold: 0
relevantTechniques:
- T1203
tags:
- CVE-2021-40444
- DEV-0413
status: Available
tactics:
- Execution
name: '[Deprecated] - MSHTML vulnerability CVE-2021-40444 attack'
id: 972c89fa-c969-4d12-932f-04d55d145299
query: |
  ( union isfuzzy=true
  (SecurityEvent
  | where EventID==4688
  | where isnotempty(CommandLine)
  | extend FileName = Process, ProcessCommandLine = CommandLine
  | where (FileName in~('control.exe','rundll32.exe') and ProcessCommandLine has '.cpl:')
    or ProcessCommandLine matches regex @'\".[a-zA-Z]{2,4}:\.\.\/\.\.'
  | extend timestamp = TimeGenerated, AccountCustomEntity = Account, HostCustomEntity = Computer
  ),
  (DeviceProcessEvents
  | where (FileName in~('control.exe','rundll32.exe') and ProcessCommandLine has '.cpl:')
  or ProcessCommandLine matches regex @'\".[a-zA-Z]{2,4}:\.\.\/\.\.'
  | extend timestamp = TimeGenerated, AccountCustomEntity = InitiatingProcessAccountUpn, HostCustomEntity = DeviceName
  ),
  (Event
  | where Source == "Microsoft-Windows-Sysmon"
  | where EventID == 1 
  | extend EventData = parse_xml(EventData).DataItem.EventData.Data
  | mv-expand bagexpansion=array EventData
  | evaluate bag_unpack(EventData)
  | extend Key = tostring(column_ifexists('@Name', "")), Value = column_ifexists('#text', "")
  | evaluate pivot(Key, any(Value), TimeGenerated, Source, EventLog, Computer, EventLevel, EventLevelName, UserName, RenderedDescription, MG, ManagementGroupName, Type, _ResourceId)
  | extend Image = column_ifexists("Image", ""), ProcessCommandLine = column_ifexists("CommandLine", "")
  | extend FileName = split(Image, '\\', -1)[-1]
  | where (FileName in~('control.exe','rundll32.exe') and ProcessCommandLine has '.cpl:')
    or ProcessCommandLine matches regex @'\".[a-zA-Z]{2,4}:\.\.\/\.\.'
  | extend timestamp = TimeGenerated, AccountCustomEntity = UserName, HostCustomEntity = Computer
  )
  )  
requiredDataConnectors:
- dataTypes:
  - SecurityEvent
  connectorId: SecurityEvents
- dataTypes:
  - DeviceProcessEvents
  connectorId: MicrosoftThreatProtection
version: 2.0.0
triggerOperator: gt
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Legacy IOC based Threat Protection/Deprecated Analytic Rules/MSHTMLVuln.yaml
queryPeriod: 1h

{
  "$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/972c89fa-c969-4d12-932f-04d55d145299')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/972c89fa-c969-4d12-932f-04d55d145299')]",
      "properties": {
        "alertRuleTemplateName": "972c89fa-c969-4d12-932f-04d55d145299",
        "customDetails": null,
        "description": "'This query has been deprecated as the associated IoCs (Indicators of Compromise) are outdated and no longer relevant. To ensure effective threat detection, it is recommended to implement Microsoft's Threat Intelligence solution, which enables matching your log data with the most up-to-date IoCs generated by Microsoft. This solution can be installed from the Microsoft Sentinel Content Hub if not currently deployed. More details on the Content Hub can be found here: https://learn.microsoft.com/azure/sentinel/sentinel-solutions-deploy'\n",
        "displayName": "[Deprecated] - MSHTML vulnerability CVE-2021-40444 attack",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "AccountCustomEntity",
                "identifier": "FullName"
              }
            ]
          },
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "HostCustomEntity",
                "identifier": "FullName"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Legacy IOC based Threat Protection/Deprecated Analytic Rules/MSHTMLVuln.yaml",
        "query": "( union isfuzzy=true\n(SecurityEvent\n| where EventID==4688\n| where isnotempty(CommandLine)\n| extend FileName = Process, ProcessCommandLine = CommandLine\n| where (FileName in~('control.exe','rundll32.exe') and ProcessCommandLine has '.cpl:')\n  or ProcessCommandLine matches regex @'\\\".[a-zA-Z]{2,4}:\\.\\.\\/\\.\\.'\n| extend timestamp = TimeGenerated, AccountCustomEntity = Account, HostCustomEntity = Computer\n),\n(DeviceProcessEvents\n| where (FileName in~('control.exe','rundll32.exe') and ProcessCommandLine has '.cpl:')\nor ProcessCommandLine matches regex @'\\\".[a-zA-Z]{2,4}:\\.\\.\\/\\.\\.'\n| extend timestamp = TimeGenerated, AccountCustomEntity = InitiatingProcessAccountUpn, HostCustomEntity = DeviceName\n),\n(Event\n| where Source == \"Microsoft-Windows-Sysmon\"\n| where EventID == 1 \n| extend EventData = parse_xml(EventData).DataItem.EventData.Data\n| mv-expand bagexpansion=array EventData\n| evaluate bag_unpack(EventData)\n| extend Key = tostring(column_ifexists('@Name', \"\")), Value = column_ifexists('#text', \"\")\n| evaluate pivot(Key, any(Value), TimeGenerated, Source, EventLog, Computer, EventLevel, EventLevelName, UserName, RenderedDescription, MG, ManagementGroupName, Type, _ResourceId)\n| extend Image = column_ifexists(\"Image\", \"\"), ProcessCommandLine = column_ifexists(\"CommandLine\", \"\")\n| extend FileName = split(Image, '\\\\', -1)[-1]\n| where (FileName in~('control.exe','rundll32.exe') and ProcessCommandLine has '.cpl:')\n  or ProcessCommandLine matches regex @'\\\".[a-zA-Z]{2,4}:\\.\\.\\/\\.\\.'\n| extend timestamp = TimeGenerated, AccountCustomEntity = UserName, HostCustomEntity = Computer\n)\n)\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "High",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Execution"
        ],
        "tags": [
          "CVE-2021-40444",
          "DEV-0413"
        ],
        "techniques": [
          "T1203"
        ],
        "templateVersion": "2.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}