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

metadata:
  categories:
    domains:
    - Security - Threat Protection
  support:
    tier: Community
  author:
    name: Yuval Naor
  source:
    kind: Community
severity: Medium
triggerOperator: gt
id: 61988db3-0565-49b5-b8e3-747195baac6e
tags:
- Id: b8266f81-2715-41a6-9062-42486cbc9c73
  version: 1.0.0
- SchemaVersion: 0.1.0
  Schema: ASIMProcessEvent
tactics:
- DefenseEvasion
triggerThreshold: 0
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  
name: Malware in the recycle bin (Normalized Process Events)
relevantTechniques:
- T1564
requiredDataConnectors: []
version: 1.2.5
queryPeriod: 1d
entityMappings:
- fieldMappings:
  - columnName: User
    identifier: FullName
  - columnName: AccountName
    identifier: Name
  - columnName: AccountNTDomain
    identifier: NTDomain
  entityType: Account
- fieldMappings:
  - columnName: Dvc
    identifier: FullName
  - columnName: HostName
    identifier: HostName
  - columnName: HostNameDomain
    identifier: DnsDomain
  entityType: Host
kind: Scheduled
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimProcess/imProcess_malware_in_recyclebin.yaml
queryFrequency: 1d
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)'

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"
    }
  ]
}