name: Windows Enable PowerShell Web Access
id: 175bb2de-6227-416b-9678-9b61999cd21f
version: 7
date: '2025-06-24'
author: Michael Haag, Splunk
data_source:
  - Powershell Script Block Logging 4104
type: TTP
status: production
description:
  The following analytic detects the enabling of PowerShell Web Access
  via PowerShell commands. It leverages PowerShell script block logging (EventCode
  4104) to identify the execution of the `Install-WindowsFeature` cmdlet with the
  `WindowsPowerShellWebAccess` parameter. This activity is significant because enabling
  PowerShell Web Access can facilitate remote execution of PowerShell commands, potentially
  allowing an attacker to gain unauthorized access to systems and networks.
search:
  '`powershell` EventCode=4104 ScriptBlockText IN ("*Install-WindowsFeature*WindowsPowerShellWebAccess*","*Install-PswaWebApplication*","*Add-PswaAuthorizationRule*UserName
  *ComputerName *") | fillnull | stats count min(_time) as firstTime max(_time) as
  lastTime by dest signature signature_id user_id vendor_product EventID Guid Opcode
  Name Path ProcessID ScriptBlockId ScriptBlockText | `security_content_ctime(firstTime)`
  | `security_content_ctime(lastTime)` | `windows_enable_powershell_web_access_filter`'
how_to_implement:
  To successfully implement this analytic, you will need to enable
  PowerShell Script Block Logging on some or all endpoints. Additional setup here
  https://help.splunk.com/en/security-offerings/splunk-user-behavior-analytics/get-data-in/5.4.1/add-other-data-to-splunk-uba/configure-powershell-logging-to-see-powershell-anomalies-in-splunk-uba.
known_false_positives:
  It is possible that legitimate scripts or network administrators
  may enable PowerShell Web Access. Monitor and escalate as needed.
references:
  - https://www.cisa.gov/news-events/cybersecurity-advisories/aa24-241a
  - https://gist.github.com/MHaggis/7e67b659af9148fa593cf2402edebb41
drilldown_searches:
  - name: View the detection results for - "$dest$"
    search: '%original_detection_search% | search  dest = "$dest$"'
    earliest_offset: $info_min_time$
    latest_offset: $info_max_time$
  - name: View risk events for the last 7 days for - "$dest$"
    search:
      '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$")
      starthoursago=168  | stats count min(_time) as firstTime max(_time) as lastTime
      values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories)
      as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic)
      as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`'
    earliest_offset: $info_min_time$
    latest_offset: $info_max_time$
rba:
  message: PowerShell Web Access has been enabled on $dest$.
  risk_objects:
    - field: dest
      type: system
      score: 72
  threat_objects: []
tags:
  analytic_story:
    - CISA AA24-241A
    - Malicious PowerShell
  asset_type: Endpoint
  mitre_attack_id:
    - T1059.001
  product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
  security_domain: endpoint
  cve: []
tests:
  - name: True Positive Test
    attack_data:
      - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1059.001/powershell_script_block_logging/pswa_powershell.log
        sourcetype: XmlWinEventLog
        source: XmlWinEventLog:Microsoft-Windows-PowerShell/Operational