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

name: Suspicious Powershell Commandlet Executed
alertDetailsOverride:
  alertDisplayNameFormat: Suspicious PowerShell Commandlet Executed on {{DvcHostname}} ({{LocalIP}}) by ({{InitiatingProcessAccountUpn}})
  alertDescriptionFormat: "Suspicious PowerShell Commandlet by Process '{{InitiatingProcessFileName}}' ProcessId: '{{InitiatingProcessId}}' with commandline {{InitiatingProcessCommandLine}} was executed."
id: b5153fb3-ada9-4ce4-9131-79c771efb50d
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.
triggerThreshold: 0
entityMappings:
- fieldMappings:
  - columnName: DeviceName
    identifier: FullName
  - columnName: DvcHostname
    identifier: HostName
  - columnName: DvcDomain
    identifier: DnsDomain
  entityType: Host
- fieldMappings:
  - columnName: LocalIP
    identifier: Address
  entityType: IP
- fieldMappings:
  - columnName: Username
    identifier: Name
  - columnName: UPNSuffix
    identifier: UPNSuffix
  entityType: Account
- fieldMappings:
  - columnName: InitiatingProcessId
    identifier: ProcessId
  - columnName: InitiatingProcessCommandLine
    identifier: CommandLine
  entityType: Process
version: 1.0.1
triggerOperator: gt
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), '.'))  
tactics:
- Execution
kind: Scheduled
queryFrequency: 1h
severity: Medium
queryPeriod: 1h
requiredDataConnectors:
- dataTypes:
  - DeviceEvents
  connectorId: MicrosoftThreatProtection
status: Available
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Endpoint Threat Protection Essentials/Analytic Rules/SuspiciousPowerShellCommandExecuted.yaml
eventGroupingSettings:
  aggregationKind: AlertPerResult
relevantTechniques:
- T1059

ARM