Potential re-named sdelete usage

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Id	720d12c6-a08c-44c4-b18f-2236412d59b0
Rulename	Potential re-named sdelete usage
Description	This detection looks for command line parameters associated with the use of Sysinternals sdelete (https://docs.microsoft.com/sysinternals/downloads/sdelete) to delete multiple files on a host’s C drive. A threat actor may re-name the tool to avoid detection and then use it for destructive attacks on a host.
Severity	Low
Tactics	DefenseEvasion Impact
Techniques	T1485 T1036
Required data connectors	SecurityEvents WindowsSecurityEvents
Kind	Scheduled
Query frequency	1h
Query period	1h
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Windows Security Events/Analytic Rules/Potentialre-namedsdeleteusage.yaml
Version	1.0.3
Arm template	720d12c6-a08c-44c4-b18f-2236412d59b0.json

KQL

SecurityEvent
  | where EventID == 4688
  | where Process !~ "sdelete.exe"
  | where CommandLine has_all ("accepteula", "-r", "-s", "-q", "c:/")
  | where CommandLine !has ("sdelete")
  | extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
  | extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
  | extend AccountName = tostring(split(TargetAccount, @'\')[1]), AccountNTDomain = tostring(split(TargetAccount, @'\')[0])

YAML

relevantTechniques:
- T1485
- T1036
name: Potential re-named sdelete usage
requiredDataConnectors:
- dataTypes:
  - SecurityEvent
  connectorId: SecurityEvents
- dataTypes:
  - SecurityEvent
  connectorId: WindowsSecurityEvents
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: TargetAccount
  - identifier: Name
    columnName: AccountName
  - identifier: NTDomain
    columnName: AccountNTDomain
  entityType: Account
- fieldMappings:
  - identifier: FullName
    columnName: Computer
  - identifier: HostName
    columnName: HostName
  - identifier: DnsDomain
    columnName: HostNameDomain
  entityType: Host
triggerThreshold: 0
id: 720d12c6-a08c-44c4-b18f-2236412d59b0
tactics:
- DefenseEvasion
- Impact
version: 1.0.3
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Windows Security Events/Analytic Rules/Potentialre-namedsdeleteusage.yaml
queryPeriod: 1h
kind: Scheduled
queryFrequency: 1h
severity: Low
status: Available
description: |
  'This detection looks for command line parameters associated with the use of Sysinternals sdelete (https://docs.microsoft.com/sysinternals/downloads/sdelete) to delete multiple files on a host's C drive.
  A threat actor may re-name the tool to avoid detection and then use it for destructive attacks on a host.'  
query: |
  SecurityEvent
    | where EventID == 4688
    | where Process !~ "sdelete.exe"
    | where CommandLine has_all ("accepteula", "-r", "-s", "-q", "c:/")
    | where CommandLine !has ("sdelete")
    | extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
    | extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
    | extend AccountName = tostring(split(TargetAccount, @'\')[1]), AccountNTDomain = tostring(split(TargetAccount, @'\')[0])  
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": "2024-01-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/720d12c6-a08c-44c4-b18f-2236412d59b0')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/720d12c6-a08c-44c4-b18f-2236412d59b0')]",
      "properties": {
        "alertRuleTemplateName": "720d12c6-a08c-44c4-b18f-2236412d59b0",
        "customDetails": null,
        "description": "'This detection looks for command line parameters associated with the use of Sysinternals sdelete (https://docs.microsoft.com/sysinternals/downloads/sdelete) to delete multiple files on a host's C drive.\nA threat actor may re-name the tool to avoid detection and then use it for destructive attacks on a host.'\n",
        "displayName": "Potential re-named sdelete usage",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "TargetAccount",
                "identifier": "FullName"
              },
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountNTDomain",
                "identifier": "NTDomain"
              }
            ]
          },
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "Computer",
                "identifier": "FullName"
              },
              {
                "columnName": "HostName",
                "identifier": "HostName"
              },
              {
                "columnName": "HostNameDomain",
                "identifier": "DnsDomain"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Windows Security Events/Analytic Rules/Potentialre-namedsdeleteusage.yaml",
        "query": "SecurityEvent\n  | where EventID == 4688\n  | where Process !~ \"sdelete.exe\"\n  | where CommandLine has_all (\"accepteula\", \"-r\", \"-s\", \"-q\", \"c:/\")\n  | where CommandLine !has (\"sdelete\")\n  | extend HostName = tostring(split(Computer, \".\")[0]), DomainIndex = toint(indexof(Computer, '.'))\n  | extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)\n  | extend AccountName = tostring(split(TargetAccount, @'\\')[1]), AccountNTDomain = tostring(split(TargetAccount, @'\\')[0])\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Low",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion",
          "Impact"
        ],
        "techniques": [
          "T1036",
          "T1485"
        ],
        "templateVersion": "1.0.3",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}