[Deprecated] - Silk Typhoon UM Service writing suspicious file

let scriptExtensions = dynamic([".php", ".jsp", ".js", ".aspx", ".asmx", ".asax", ".cfm", ".shtml"]);
union isfuzzy=true
(SecurityEvent
| where EventID == 4663
| where Process has_any ("umworkerprocess.exe", "UMService.exe")
| where ObjectName has_any (scriptExtensions)
| where AccessMask in ('0x2','0x100', '0x10', '0x4')
| extend timestamp = TimeGenerated, AccountCustomEntity = Account, HostCustomEntity = Computer, IPCustomEntity = IpAddress
),
  (WindowsEvent
| where EventID == 4663 and EventData has_any ("umworkerprocess.exe", "UMService.exe") and EventData has_any (scriptExtensions) 
| where EventData has_any ('0x2','0x100', '0x10', '0x4')
| extend NewProcessName = tostring(EventData.NewProcessName)
| extend Process=tostring(split(NewProcessName, '\\')[-1])
| where Process has_any ("umworkerprocess.exe", "UMService.exe")
| extend ObjectName = tostring(EventData.ObjectName)
| where ObjectName has_any (scriptExtensions)
| extend AccessMask = tostring(EventData.AccessMask)
| where AccessMask in ('0x2','0x100', '0x10', '0x4')
| extend Account = strcat(EventData.SubjectDomainName,"\\", EventData.SubjectUserName)
| extend IpAddress = tostring(EventData.IpAddress)
| extend timestamp = TimeGenerated, AccountCustomEntity = Account, HostCustomEntity = Computer, IPCustomEntity = IpAddress
),
(imFileEvent
| where EventType == "FileCreated"
| where ActingProcessName has_any ("umworkerprocess.exe", "UMService.exe")
  and
  TargetFileName has_any (scriptExtensions)
| extend timestamp = TimeGenerated, AccountCustomEntity = ActorUsername, HostCustomEntity = DvcHostname
),
(DeviceFileEvents
| where ActionType =~ "FileCreated"
| where InitiatingProcessFileName has_any ("umworkerprocess.exe", "UMService.exe")
| where FileName has_any(scriptExtensions)
| extend timestamp = TimeGenerated, AccountCustomEntity = InitiatingProcessAccountUpn, HostCustomEntity = DeviceName, IPCustomEntity = RequestSourceIP)

id: 7d6d8a8e-b08a-4082-8dbb-d7fd2cbbc35e
tactics:
- InitialAccess
queryPeriod: 1d
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Legacy IOC based Threat Protection/Deprecated Analytic Rules/SilkTyphoonUmServiceSuspiciousFile.yaml
triggerThreshold: 0
name: '[Deprecated] - Silk Typhoon UM Service writing suspicious file'
query: |
  let scriptExtensions = dynamic([".php", ".jsp", ".js", ".aspx", ".asmx", ".asax", ".cfm", ".shtml"]);
  union isfuzzy=true
  (SecurityEvent
  | where EventID == 4663
  | where Process has_any ("umworkerprocess.exe", "UMService.exe")
  | where ObjectName has_any (scriptExtensions)
  | where AccessMask in ('0x2','0x100', '0x10', '0x4')
  | extend timestamp = TimeGenerated, AccountCustomEntity = Account, HostCustomEntity = Computer, IPCustomEntity = IpAddress
  ),
    (WindowsEvent
  | where EventID == 4663 and EventData has_any ("umworkerprocess.exe", "UMService.exe") and EventData has_any (scriptExtensions) 
  | where EventData has_any ('0x2','0x100', '0x10', '0x4')
  | extend NewProcessName = tostring(EventData.NewProcessName)
  | extend Process=tostring(split(NewProcessName, '\\')[-1])
  | where Process has_any ("umworkerprocess.exe", "UMService.exe")
  | extend ObjectName = tostring(EventData.ObjectName)
  | where ObjectName has_any (scriptExtensions)
  | extend AccessMask = tostring(EventData.AccessMask)
  | where AccessMask in ('0x2','0x100', '0x10', '0x4')
  | extend Account = strcat(EventData.SubjectDomainName,"\\", EventData.SubjectUserName)
  | extend IpAddress = tostring(EventData.IpAddress)
  | extend timestamp = TimeGenerated, AccountCustomEntity = Account, HostCustomEntity = Computer, IPCustomEntity = IpAddress
  ),
  (imFileEvent
  | where EventType == "FileCreated"
  | where ActingProcessName has_any ("umworkerprocess.exe", "UMService.exe")
    and
    TargetFileName has_any (scriptExtensions)
  | extend timestamp = TimeGenerated, AccountCustomEntity = ActorUsername, HostCustomEntity = DvcHostname
  ),
  (DeviceFileEvents
  | where ActionType =~ "FileCreated"
  | where InitiatingProcessFileName has_any ("umworkerprocess.exe", "UMService.exe")
  | where FileName has_any(scriptExtensions)
  | extend timestamp = TimeGenerated, AccountCustomEntity = InitiatingProcessAccountUpn, HostCustomEntity = DeviceName, IPCustomEntity = RequestSourceIP)  
severity: High
triggerOperator: gt
kind: Scheduled
relevantTechniques:
- T1190
tags:
- SchemaVersion: 0.1.0
  Schema: ASIMFileEvent
queryFrequency: 1d
requiredDataConnectors:
- connectorId: SecurityEvents
  dataTypes:
  - SecurityEvent
- connectorId: MicrosoftThreatProtection
  dataTypes:
  - DeviceFileEvents
- connectorId: WindowsSecurityEvents
  dataTypes:
  - SecurityEvents
- connectorId: WindowsForwardedEvents
  dataTypes:
  - WindowsEvent
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'
status: Available
version: 2.0.0
entityMappings:
- fieldMappings:
  - columnName: InitiatingProcessAccountUpn
    identifier: FullName
  entityType: Account
- fieldMappings:
  - columnName: AccountCustomEntity
    identifier: FullName
  entityType: Account
- fieldMappings:
  - columnName: HostCustomEntity
    identifier: FullName
  entityType: Host
- fieldMappings:
  - columnName: DeviceName
    identifier: FullName
  entityType: Host
- fieldMappings:
  - columnName: IPCustomEntity
    identifier: Address
  entityType: IP

{
  "$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/7d6d8a8e-b08a-4082-8dbb-d7fd2cbbc35e')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/7d6d8a8e-b08a-4082-8dbb-d7fd2cbbc35e')]",
      "properties": {
        "alertRuleTemplateName": "7d6d8a8e-b08a-4082-8dbb-d7fd2cbbc35e",
        "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] - Silk Typhoon UM Service writing suspicious file",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "InitiatingProcessAccountUpn",
                "identifier": "FullName"
              }
            ]
          },
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "AccountCustomEntity",
                "identifier": "FullName"
              }
            ]
          },
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "HostCustomEntity",
                "identifier": "FullName"
              }
            ]
          },
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "DeviceName",
                "identifier": "FullName"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "IPCustomEntity",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Legacy IOC based Threat Protection/Deprecated Analytic Rules/SilkTyphoonUmServiceSuspiciousFile.yaml",
        "query": "let scriptExtensions = dynamic([\".php\", \".jsp\", \".js\", \".aspx\", \".asmx\", \".asax\", \".cfm\", \".shtml\"]);\nunion isfuzzy=true\n(SecurityEvent\n| where EventID == 4663\n| where Process has_any (\"umworkerprocess.exe\", \"UMService.exe\")\n| where ObjectName has_any (scriptExtensions)\n| where AccessMask in ('0x2','0x100', '0x10', '0x4')\n| extend timestamp = TimeGenerated, AccountCustomEntity = Account, HostCustomEntity = Computer, IPCustomEntity = IpAddress\n),\n  (WindowsEvent\n| where EventID == 4663 and EventData has_any (\"umworkerprocess.exe\", \"UMService.exe\") and EventData has_any (scriptExtensions) \n| where EventData has_any ('0x2','0x100', '0x10', '0x4')\n| extend NewProcessName = tostring(EventData.NewProcessName)\n| extend Process=tostring(split(NewProcessName, '\\\\')[-1])\n| where Process has_any (\"umworkerprocess.exe\", \"UMService.exe\")\n| extend ObjectName = tostring(EventData.ObjectName)\n| where ObjectName has_any (scriptExtensions)\n| extend AccessMask = tostring(EventData.AccessMask)\n| where AccessMask in ('0x2','0x100', '0x10', '0x4')\n| extend Account = strcat(EventData.SubjectDomainName,\"\\\\\", EventData.SubjectUserName)\n| extend IpAddress = tostring(EventData.IpAddress)\n| extend timestamp = TimeGenerated, AccountCustomEntity = Account, HostCustomEntity = Computer, IPCustomEntity = IpAddress\n),\n(imFileEvent\n| where EventType == \"FileCreated\"\n| where ActingProcessName has_any (\"umworkerprocess.exe\", \"UMService.exe\")\n  and\n  TargetFileName has_any (scriptExtensions)\n| extend timestamp = TimeGenerated, AccountCustomEntity = ActorUsername, HostCustomEntity = DvcHostname\n),\n(DeviceFileEvents\n| where ActionType =~ \"FileCreated\"\n| where InitiatingProcessFileName has_any (\"umworkerprocess.exe\", \"UMService.exe\")\n| where FileName has_any(scriptExtensions)\n| extend timestamp = TimeGenerated, AccountCustomEntity = InitiatingProcessAccountUpn, HostCustomEntity = DeviceName, IPCustomEntity = RequestSourceIP)\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "High",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "InitialAccess"
        ],
        "tags": [
          {
            "Schema": "ASIMFileEvent",
            "SchemaVersion": "0.1.0"
          }
        ],
        "techniques": [
          "T1190"
        ],
        "templateVersion": "2.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}