Deletion of data on multiple drives using cipher exe

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Id	03caa992-477f-4b19-8e2a-8cd58f8f9652
Rulename	Deletion of data on multiple drives using cipher exe
Description	This query checks for attempts to delete data on multiple drives using cipher.exe. This activity is typically done by ransomware to prevent recovery of data after encryption.
Severity	Medium
Tactics	Impact
Techniques	T1485
Required data connectors	MicrosoftThreatProtection
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/Microsoft Defender XDR/Analytic Rules/Ransomware/DataDeletionOnMulipleDrivesUsingCipherExe.yaml
Version	1.0.0
Arm template	03caa992-477f-4b19-8e2a-8cd58f8f9652.json

KQL

// Look for cipher.exe deleting data from multiple drives
DeviceProcessEvents
| where FileName =~ "cipher.exe" 
// cipher.exe /w flag used for deleting data 
| where ProcessCommandLine has "/w" 
| summarize CipherCount = dcount(ProcessCommandLine), CipherList = make_set(ProcessCommandLine, 1000) by DeviceId, DeviceName, bin(TimeGenerated, 1m) 
// cipher.exe accessing multiple drives in a short timeframe  
| where CipherCount > 1
| extend HostName = iff(DeviceName has '.', substring(DeviceName, 0, indexof(DeviceName, '.')), DeviceName)
| extend DnsDomain = iff(DeviceName has '.', substring(DeviceName, indexof(DeviceName, '.') + 1), "")

YAML

severity: Medium
relevantTechniques:
- T1485
queryFrequency: 1h
kind: Scheduled
version: 1.0.0
name: Deletion of data on multiple drives using cipher exe
triggerOperator: gt
description: |
    This query checks for attempts to delete data on multiple drives using cipher.exe. This activity is typically done by ransomware to prevent recovery of data after encryption.
queryPeriod: 1h
query: |
  // Look for cipher.exe deleting data from multiple drives
  DeviceProcessEvents
  | where FileName =~ "cipher.exe" 
  // cipher.exe /w flag used for deleting data 
  | where ProcessCommandLine has "/w" 
  | summarize CipherCount = dcount(ProcessCommandLine), CipherList = make_set(ProcessCommandLine, 1000) by DeviceId, DeviceName, bin(TimeGenerated, 1m) 
  // cipher.exe accessing multiple drives in a short timeframe  
  | where CipherCount > 1
  | extend HostName = iff(DeviceName has '.', substring(DeviceName, 0, indexof(DeviceName, '.')), DeviceName)
  | extend DnsDomain = iff(DeviceName has '.', substring(DeviceName, indexof(DeviceName, '.') + 1), "")  
entityMappings:
- entityType: Host
  fieldMappings:
  - columnName: DeviceName
    identifier: FullName
  - columnName: HostName
    identifier: HostName
  - columnName: DnsDomain
    identifier: DnsDomain
tactics:
- Impact
status: Available
triggerThreshold: 0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Defender XDR/Analytic Rules/Ransomware/DataDeletionOnMulipleDrivesUsingCipherExe.yaml
id: 03caa992-477f-4b19-8e2a-8cd58f8f9652
requiredDataConnectors:
- dataTypes:
  - DeviceProcessEvents
  connectorId: MicrosoftThreatProtection

ARM

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2023-02-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/03caa992-477f-4b19-8e2a-8cd58f8f9652')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/03caa992-477f-4b19-8e2a-8cd58f8f9652')]",
      "properties": {
        "alertRuleTemplateName": "03caa992-477f-4b19-8e2a-8cd58f8f9652",
        "customDetails": null,
        "description": "This query checks for attempts to delete data on multiple drives using cipher.exe. This activity is typically done by ransomware to prevent recovery of data after encryption.\n",
        "displayName": "Deletion of data on multiple drives using cipher exe",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "DeviceName",
                "identifier": "FullName"
              },
              {
                "columnName": "HostName",
                "identifier": "HostName"
              },
              {
                "columnName": "DnsDomain",
                "identifier": "DnsDomain"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Defender XDR/Analytic Rules/Ransomware/DataDeletionOnMulipleDrivesUsingCipherExe.yaml",
        "query": "// Look for cipher.exe deleting data from multiple drives\nDeviceProcessEvents\n| where FileName =~ \"cipher.exe\" \n// cipher.exe /w flag used for deleting data \n| where ProcessCommandLine has \"/w\" \n| summarize CipherCount = dcount(ProcessCommandLine), CipherList = make_set(ProcessCommandLine, 1000) by DeviceId, DeviceName, bin(TimeGenerated, 1m) \n// cipher.exe accessing multiple drives in a short timeframe  \n| where CipherCount > 1\n| extend HostName = iff(DeviceName has '.', substring(DeviceName, 0, indexof(DeviceName, '.')), DeviceName)\n| extend DnsDomain = iff(DeviceName has '.', substring(DeviceName, indexof(DeviceName, '.') + 1), \"\")\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Impact"
        ],
        "techniques": [
          "T1485"
        ],
        "templateVersion": "1.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}