Windows Renamed Powershell Execution

SPLUNK detection rule by Teoderick Contreras, Nasreddine Bencherchali, Splunk · Apache-2.0

The following analytic identifies instances where the PowerShell executable has been renamed and executed under an alternate filename. This behavior is commonly associated with attempts to evade security controls or bypass logging mechanisms that monitor standard PowerShell usage. While rare in legitimate environments, renamed PowerShell binaries are frequently observed in malicious campaigns leveraging Living-off-the-Land Binaries (LOLBins) and fileless malware techniques. This detection flags executions of PowerShell where the process name does not match the default powershell.exe or pwsh.exe, especially when invoked from unusual paths or accompanied by suspicious command-line arguments.

name: Windows Renamed Powershell Execution
id: c08014de-cc5a-42de-9775-76ecd5b37bbd
version: 8
creation_date: '2022-10-27'
modification_date: '2026-05-13'
author: Teoderick Contreras, Nasreddine Bencherchali, Splunk
status: production
type: TTP
description: The following analytic identifies instances where the PowerShell executable has been renamed and executed under an alternate filename. This behavior is commonly associated with attempts to evade security controls or bypass logging mechanisms that monitor standard PowerShell usage. While rare in legitimate environments, renamed PowerShell binaries are frequently observed in malicious campaigns leveraging Living-off-the-Land Binaries (LOLBins) and fileless malware techniques. This detection flags executions of PowerShell where the process name does not match the default powershell.exe or pwsh.exe, especially when invoked from unusual paths or accompanied by suspicious command-line arguments.
data_source:
    - Sysmon EventID 1
search: "| tstats `security_content_summariesonly`\n  count min(_time) as firstTime\n        max(_time) as lastTime\n\nfrom datamodel=Endpoint.Processes where\n\n(\n  Processes.original_file_name = PowerShell.EXE\n  Processes.process_name != powershell.exe\n)\nOR\n(\n  Processes.original_file_name = pwsh.dll\n  Processes.process_name != pwsh.exe\n)\nOR\n(\n  Processes.original_file_name = powershell_ise.EXE\n  Processes.process_name != powershell_ise.exe\n)\n\nby Processes.action Processes.dest Processes.original_file_name Processes.parent_process\n   Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id\n   Processes.parent_process_name Processes.parent_process_path Processes.process\n   Processes.process_exec Processes.process_guid Processes.process_hash Processes.process_id\n   Processes.process_integrity_level Processes.process_name Processes.process_path Processes.user\n   Processes.user_id Processes.vendor_product\n\n| `drop_dm_object_name(Processes)`\n| `security_content_ctime(firstTime)`\n| `security_content_ctime(lastTime)`\n| `windows_renamed_powershell_execution_filter`\n"
how_to_implement: The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint` data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.
known_false_positives: No false positives have been identified at this time.
references:
    - https://malpedia.caad.fkie.fraunhofer.de/details/win.xworm
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 ("$dest$") | 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: 7d
      latest_offset: '0'
finding:
    title: powershell was renamed as $process_name$ on $dest$
    entity:
        field: dest
        type: system
        score: 50
analytic_story:
    - XWorm
    - Hellcat Ransomware
    - Axios Supply Chain Post Compromise
asset_type: Endpoint
mitre_attack_id:
    - T1036.003
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1036.003/renamed_powershell/renamed_powershell.log
          source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
          sourcetype: XmlWinEventLog
      test_type: unit

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

689bcf5f-13aa-40d0-a0e8-8aab016f521a

Propose edits, view related rules, and engage with the community through comments.

Executable code, not a declarative rule

This submission is arbitrary [[ currentRule.format ? currentRule.format.toUpperCase() : '' ]] code, not a declarative detection rule — review it as you would any script before running it, and note that it cannot be safely aggregated or auto-executed alongside YARA/Sigma/Suricata/CRS rules.

Rejected pattern present

[[ reason ]]

What does this mean?

Format & documentation suggestions

Not a security issue — this rule is valid and was accepted as-is. These are optional fields/conventions its own format recommends, mainly affecting its quality score and how well it documents itself for other reviewers.

[[ reason ]]

What do these messages mean?

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

[[ currentRule.title ]]

Community Discussion