Potential re-named sdelete usage ASIM Version

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Id	5b6ae038-f66e-4f74-9315-df52fd492be4
Rulename	Potential re-named sdelete usage (ASIM Version)
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. This detection uses the ASIM imProcess parser, this will need to be deployed before use - https://docs.microsoft.com/azure/sentinel/normalization
Severity	Low
Tactics	DefenseEvasion Impact
Techniques	T1485 T1036
Kind	Scheduled
Query frequency	1h
Query period	1h
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimProcess/Potentialre-namedsdeleteusage(ASIMVersion).yaml
Version	1.0.6
Arm template	5b6ae038-f66e-4f74-9315-df52fd492be4.json

KQL

imProcess
| where CommandLine has_all ("accepteula", "-s", "-r", "-q")
| where Process !endswith "sdelete.exe"
| where CommandLine !has "sdelete"
| extend AccountName = tostring(split(ActorUsername, @'\')[1]), AccountNTDomain = tostring(split(ActorUsername, @'\')[0])

YAML

queryPeriod: 1h
queryFrequency: 1h
name: Potential re-named sdelete usage (ASIM Version)
id: 5b6ae038-f66e-4f74-9315-df52fd492be4
entityMappings:
- entityType: Account
  fieldMappings:
  - columnName: ActorUsername
    identifier: FullName
  - columnName: AccountName
    identifier: Name
  - columnName: AccountNTDomain
    identifier: NTDomain
- entityType: Host
  fieldMappings:
  - columnName: Dvc
    identifier: FullName
  - columnName: DvcHostname
    identifier: HostName
  - columnName: DvcDomain
    identifier: DnsDomain
- entityType: IP
  fieldMappings:
  - columnName: DvcIpAddr
    identifier: Address
query: |
  imProcess
  | where CommandLine has_all ("accepteula", "-s", "-r", "-q")
  | where Process !endswith "sdelete.exe"
  | where CommandLine !has "sdelete"
  | extend AccountName = tostring(split(ActorUsername, @'\')[1]), AccountNTDomain = tostring(split(ActorUsername, @'\')[0])  
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimProcess/Potentialre-namedsdeleteusage(ASIMVersion).yaml
requiredDataConnectors: []
relevantTechniques:
- T1485
- T1036
metadata:
  support:
    tier: Community
  categories:
    domains:
    - Security - Threat Protection
  source:
    kind: Community
  author:
    name: Microsoft Security Research
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.
  This detection uses the ASIM imProcess parser, this will need to be deployed before use - https://docs.microsoft.com/azure/sentinel/normalization'  
tactics:
- DefenseEvasion
- Impact
severity: Low
triggerThreshold: 0
version: 1.0.6
kind: Scheduled
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/5b6ae038-f66e-4f74-9315-df52fd492be4')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/5b6ae038-f66e-4f74-9315-df52fd492be4')]",
      "properties": {
        "alertRuleTemplateName": "5b6ae038-f66e-4f74-9315-df52fd492be4",
        "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.\nThis detection uses the ASIM imProcess parser, this will need to be deployed before use - https://docs.microsoft.com/azure/sentinel/normalization'\n",
        "displayName": "Potential re-named sdelete usage (ASIM Version)",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "ActorUsername",
                "identifier": "FullName"
              },
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountNTDomain",
                "identifier": "NTDomain"
              }
            ]
          },
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "Dvc",
                "identifier": "FullName"
              },
              {
                "columnName": "DvcHostname",
                "identifier": "HostName"
              },
              {
                "columnName": "DvcDomain",
                "identifier": "DnsDomain"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "DvcIpAddr",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimProcess/Potentialre-namedsdeleteusage(ASIMVersion).yaml",
        "query": "imProcess\n| where CommandLine has_all (\"accepteula\", \"-s\", \"-r\", \"-q\")\n| where Process !endswith \"sdelete.exe\"\n| where CommandLine !has \"sdelete\"\n| extend AccountName = tostring(split(ActorUsername, @'\\')[1]), AccountNTDomain = tostring(split(ActorUsername, @'\\')[0])\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Low",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion",
          "Impact"
        ],
        "techniques": [
          "T1036",
          "T1485"
        ],
        "templateVersion": "1.0.6",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}