Name:Windows Renamed Powershell Execution id:c08014de-cc5a-42de-9775-76ecd5b37bbd version:1 date:2025-05-07 author:Teoderick Contreras, 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` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_name!=powershell.exe AND Processes.process_name!=pwsh.exe AND Processes.original_file_name=powershell.EXE by Processes.action Processes.dest Processes.original_file_name Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path Processes.process Processes.process_exec Processes.process_guid Processes.process_hash Processes.process_id Processes.process_integrity_level Processes.process_name Processes.process_path Processes.user Processes.user_id Processes.vendor_product | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `windows_renamed_powershell_execution_filter`
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:unknown 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 ("$dest$") 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:'$info_max_time$' tags: analytic_story: - 'XWorm' asset_type:Endpoint mitre_attack_id: - 'T1036.003' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' security_domain:endpoint
