Malware in the recycle bin Normalized Process Events

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Id	61988db3-0565-49b5-b8e3-747195baac6e
Rulename	Malware in the recycle bin (Normalized Process Events)
Description	Identifies malware that has been hidden in the recycle bin. To use this analytics rule, make sure you have deployed the ASIM normalization parsers
Severity	Medium
Tactics	DefenseEvasion
Techniques	T1564
Kind	Scheduled
Query frequency	1d
Query period	1d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimProcess/imProcess_malware_in_recyclebin.yaml
Version	1.2.5
Arm template	61988db3-0565-49b5-b8e3-747195baac6e.json

KQL

let procList = dynamic(["cmd.exe","ftp.exe","schtasks.exe","powershell.exe","rundll32.exe","regsvr32.exe","msiexec.exe"]);  
imProcessCreate
| where CommandLine has "recycler"
| where Process has_any (procList)
| extend FileName = tostring(split(Process, '\\')[-1])
| where FileName in~ (procList)
| project TimeGenerated, Dvc, User, Process, FileName, CommandLine, ActingProcessName, EventVendor, EventProduct
| extend AccountName = tostring(split(User, @'\')[1]), AccountNTDomain = tostring(split(User, @'\')[0])
| extend HostName = tostring(split(Dvc, ".")[0]), DomainIndex = toint(indexof(Dvc, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)
| project-away DomainIndex

YAML

relevantTechniques:
- T1564
name: Malware in the recycle bin (Normalized Process Events)
requiredDataConnectors: []
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: User
  - identifier: Name
    columnName: AccountName
  - identifier: NTDomain
    columnName: AccountNTDomain
  entityType: Account
- fieldMappings:
  - identifier: FullName
    columnName: Dvc
  - identifier: HostName
    columnName: HostName
  - identifier: DnsDomain
    columnName: HostNameDomain
  entityType: Host
triggerThreshold: 0
id: 61988db3-0565-49b5-b8e3-747195baac6e
tactics:
- DefenseEvasion
version: 1.2.5
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimProcess/imProcess_malware_in_recyclebin.yaml
queryPeriod: 1d
kind: Scheduled
tags:
- Id: b8266f81-2715-41a6-9062-42486cbc9c73
  version: 1.0.0
- Schema: ASIMProcessEvent
  SchemaVersion: 0.1.0
metadata:
  categories:
    domains:
    - Security - Threat Protection
  author:
    name: Yuval Naor
  support:
    tier: Community
  source:
    kind: Community
queryFrequency: 1d
severity: Medium
description: |
  'Identifies malware that has been hidden in the recycle bin.
  To use this analytics rule, make sure you have deployed the [ASIM normalization parsers](https://aka.ms/ASimProcessEvent)'  
query: |
  let procList = dynamic(["cmd.exe","ftp.exe","schtasks.exe","powershell.exe","rundll32.exe","regsvr32.exe","msiexec.exe"]);  
  imProcessCreate
  | where CommandLine has "recycler"
  | where Process has_any (procList)
  | extend FileName = tostring(split(Process, '\\')[-1])
  | where FileName in~ (procList)
  | project TimeGenerated, Dvc, User, Process, FileName, CommandLine, ActingProcessName, EventVendor, EventProduct
  | extend AccountName = tostring(split(User, @'\')[1]), AccountNTDomain = tostring(split(User, @'\')[0])
  | extend HostName = tostring(split(Dvc, ".")[0]), DomainIndex = toint(indexof(Dvc, '.'))
  | extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)
  | project-away DomainIndex  
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/61988db3-0565-49b5-b8e3-747195baac6e')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/61988db3-0565-49b5-b8e3-747195baac6e')]",
      "properties": {
        "alertRuleTemplateName": "61988db3-0565-49b5-b8e3-747195baac6e",
        "customDetails": null,
        "description": "'Identifies malware that has been hidden in the recycle bin.\nTo use this analytics rule, make sure you have deployed the [ASIM normalization parsers](https://aka.ms/ASimProcessEvent)'\n",
        "displayName": "Malware in the recycle bin (Normalized Process Events)",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "User",
                "identifier": "FullName"
              },
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountNTDomain",
                "identifier": "NTDomain"
              }
            ]
          },
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "Dvc",
                "identifier": "FullName"
              },
              {
                "columnName": "HostName",
                "identifier": "HostName"
              },
              {
                "columnName": "HostNameDomain",
                "identifier": "DnsDomain"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimProcess/imProcess_malware_in_recyclebin.yaml",
        "query": "let procList = dynamic([\"cmd.exe\",\"ftp.exe\",\"schtasks.exe\",\"powershell.exe\",\"rundll32.exe\",\"regsvr32.exe\",\"msiexec.exe\"]);  \nimProcessCreate\n| where CommandLine has \"recycler\"\n| where Process has_any (procList)\n| extend FileName = tostring(split(Process, '\\\\')[-1])\n| where FileName in~ (procList)\n| project TimeGenerated, Dvc, User, Process, FileName, CommandLine, ActingProcessName, EventVendor, EventProduct\n| extend AccountName = tostring(split(User, @'\\')[1]), AccountNTDomain = tostring(split(User, @'\\')[0])\n| extend HostName = tostring(split(Dvc, \".\")[0]), DomainIndex = toint(indexof(Dvc, '.'))\n| extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)\n| project-away DomainIndex\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Medium",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "tags": [
          {
            "Id": "b8266f81-2715-41a6-9062-42486cbc9c73",
            "version": "1.0.0"
          },
          {
            "Schema": "ASIMProcessEvent",
            "SchemaVersion": "0.1.0"
          }
        ],
        "techniques": [
          "T1564"
        ],
        "templateVersion": "1.2.5",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}