Suspicious Powershell Commandlet Executed

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Id	b5153fb3-ada9-4ce4-9131-79c771efb50d
Rulename	Suspicious Powershell Commandlet Executed
Description	This analytic rule detects when a suspicious PowerShell commandlet is executed on a host. Threat actors often use PowerShell to execute commands and scripts to move laterally, escalate privileges, and exfiltrate data.
Severity	Medium
Tactics	Execution
Techniques	T1059
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/Endpoint Threat Protection Essentials/Analytic Rules/SuspiciousPowerShellCommandExecuted.yaml
Version	1.0.1
Arm template	b5153fb3-ada9-4ce4-9131-79c771efb50d.json

KQL

// Adjust the list of suspicious commandlets as needed
let SuspiciousPowerShellCommandList = dynamic(["Get-ADUserResultantPasswordPolicy",
  "Get-DomainPolicy",
  "Get-DomainUser",
  "Get-DomainComputer",
  "Get-DomainController",
  "Get-DomainGroup",
  "Get-DomainTrust",
  "Get-ADTrust",
  "Get-ForestTrust"
  ]);
DeviceEvents
| where ActionType == "PowerShellCommand"
| extend Commandlet = tostring(parse_json(AdditionalFields).Command)
| where Commandlet has_any (SuspiciousPowerShellCommandList)
| project TimeGenerated, DeviceName, LocalIP, InitiatingProcessAccountUpn, InitiatingProcessId, InitiatingProcessFileName, InitiatingProcessFolderPath, InitiatingProcessCommandLine
| extend Username = tostring(split(InitiatingProcessAccountUpn, '@')[0]), UPNSuffix = tostring(split(InitiatingProcessAccountUpn, '@')[1])
| extend DvcHostname = tostring(split(DeviceName, '.')[0]), DvcDomain = tostring(strcat_array(array_slice(split(DeviceName, '.'), 1, -1), '.'))

YAML

triggerOperator: gt
queryFrequency: 1h
description: |
    This analytic rule detects when a suspicious PowerShell commandlet is executed on a host. Threat actors often use PowerShell to execute commands and scripts to move laterally, escalate privileges, and exfiltrate data.
status: Available
kind: Scheduled
triggerThreshold: 0
requiredDataConnectors:
- connectorId: MicrosoftThreatProtection
  dataTypes:
  - DeviceEvents
version: 1.0.1
eventGroupingSettings:
  aggregationKind: AlertPerResult
queryPeriod: 1h
name: Suspicious Powershell Commandlet Executed
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Endpoint Threat Protection Essentials/Analytic Rules/SuspiciousPowerShellCommandExecuted.yaml
id: b5153fb3-ada9-4ce4-9131-79c771efb50d
alertDetailsOverride:
  alertDescriptionFormat: "Suspicious PowerShell Commandlet by Process '{{InitiatingProcessFileName}}' ProcessId: '{{InitiatingProcessId}}' with commandline {{InitiatingProcessCommandLine}} was executed."
  alertDisplayNameFormat: Suspicious PowerShell Commandlet Executed on {{DvcHostname}} ({{LocalIP}}) by ({{InitiatingProcessAccountUpn}})
tactics:
- Execution
relevantTechniques:
- T1059
severity: Medium
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: DeviceName
  - identifier: HostName
    columnName: DvcHostname
  - identifier: DnsDomain
    columnName: DvcDomain
  entityType: Host
- fieldMappings:
  - identifier: Address
    columnName: LocalIP
  entityType: IP
- fieldMappings:
  - identifier: Name
    columnName: Username
  - identifier: UPNSuffix
    columnName: UPNSuffix
  entityType: Account
- fieldMappings:
  - identifier: ProcessId
    columnName: InitiatingProcessId
  - identifier: CommandLine
    columnName: InitiatingProcessCommandLine
  entityType: Process
query: |
  // Adjust the list of suspicious commandlets as needed
  let SuspiciousPowerShellCommandList = dynamic(["Get-ADUserResultantPasswordPolicy",
    "Get-DomainPolicy",
    "Get-DomainUser",
    "Get-DomainComputer",
    "Get-DomainController",
    "Get-DomainGroup",
    "Get-DomainTrust",
    "Get-ADTrust",
    "Get-ForestTrust"
    ]);
  DeviceEvents
  | where ActionType == "PowerShellCommand"
  | extend Commandlet = tostring(parse_json(AdditionalFields).Command)
  | where Commandlet has_any (SuspiciousPowerShellCommandList)
  | project TimeGenerated, DeviceName, LocalIP, InitiatingProcessAccountUpn, InitiatingProcessId, InitiatingProcessFileName, InitiatingProcessFolderPath, InitiatingProcessCommandLine
  | extend Username = tostring(split(InitiatingProcessAccountUpn, '@')[0]), UPNSuffix = tostring(split(InitiatingProcessAccountUpn, '@')[1])
  | extend DvcHostname = tostring(split(DeviceName, '.')[0]), DvcDomain = tostring(strcat_array(array_slice(split(DeviceName, '.'), 1, -1), '.'))

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/b5153fb3-ada9-4ce4-9131-79c771efb50d')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/b5153fb3-ada9-4ce4-9131-79c771efb50d')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "Suspicious PowerShell Commandlet by Process '{{InitiatingProcessFileName}}' ProcessId: '{{InitiatingProcessId}}' with commandline {{InitiatingProcessCommandLine}} was executed.",
          "alertDisplayNameFormat": "Suspicious PowerShell Commandlet Executed on {{DvcHostname}} ({{LocalIP}}) by ({{InitiatingProcessAccountUpn}})"
        },
        "alertRuleTemplateName": "b5153fb3-ada9-4ce4-9131-79c771efb50d",
        "customDetails": null,
        "description": "This analytic rule detects when a suspicious PowerShell commandlet is executed on a host. Threat actors often use PowerShell to execute commands and scripts to move laterally, escalate privileges, and exfiltrate data.\n",
        "displayName": "Suspicious Powershell Commandlet Executed",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "DeviceName",
                "identifier": "FullName"
              },
              {
                "columnName": "DvcHostname",
                "identifier": "HostName"
              },
              {
                "columnName": "DvcDomain",
                "identifier": "DnsDomain"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "LocalIP",
                "identifier": "Address"
              }
            ]
          },
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "Username",
                "identifier": "Name"
              },
              {
                "columnName": "UPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "Process",
            "fieldMappings": [
              {
                "columnName": "InitiatingProcessId",
                "identifier": "ProcessId"
              },
              {
                "columnName": "InitiatingProcessCommandLine",
                "identifier": "CommandLine"
              }
            ]
          }
        ],
        "eventGroupingSettings": {
          "aggregationKind": "AlertPerResult"
        },
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Endpoint Threat Protection Essentials/Analytic Rules/SuspiciousPowerShellCommandExecuted.yaml",
        "query": "// Adjust the list of suspicious commandlets as needed\nlet SuspiciousPowerShellCommandList = dynamic([\"Get-ADUserResultantPasswordPolicy\",\n  \"Get-DomainPolicy\",\n  \"Get-DomainUser\",\n  \"Get-DomainComputer\",\n  \"Get-DomainController\",\n  \"Get-DomainGroup\",\n  \"Get-DomainTrust\",\n  \"Get-ADTrust\",\n  \"Get-ForestTrust\"\n  ]);\nDeviceEvents\n| where ActionType == \"PowerShellCommand\"\n| extend Commandlet = tostring(parse_json(AdditionalFields).Command)\n| where Commandlet has_any (SuspiciousPowerShellCommandList)\n| project TimeGenerated, DeviceName, LocalIP, InitiatingProcessAccountUpn, InitiatingProcessId, InitiatingProcessFileName, InitiatingProcessFolderPath, InitiatingProcessCommandLine\n| extend Username = tostring(split(InitiatingProcessAccountUpn, '@')[0]), UPNSuffix = tostring(split(InitiatingProcessAccountUpn, '@')[1])\n| extend DvcHostname = tostring(split(DeviceName, '.')[0]), DvcDomain = tostring(strcat_array(array_slice(split(DeviceName, '.'), 1, -1), '.'))\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Execution"
        ],
        "techniques": [
          "T1059"
        ],
        "templateVersion": "1.0.1",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}