Windows Shell Process from CrushFTP

 Original Source: [splunk source]
Name:Windows Shell Process from CrushFTP
id:459628e3-1b00-4e9b-9e5b-7da8961aea35
version:7
date:None
author:Michael Haag, Splunk
status:production
type:TTP
Description:The following analytic identifies instances where CrushFTP's service process (crushftpservice.exe) spawns shell processes like cmd.exe or powershell.exe. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process creation events. This activity is significant because CrushFTP should not normally spawn interactive shell processes during regular operations. If confirmed malicious, this behavior could indicate successful exploitation of vulnerabilities like CVE-2025-31161, potentially allowing attackers to execute arbitrary commands with the privileges of the CrushFTP service.
Data_source:
  • -Sysmon EventID 1
  • -Windows Event Log Security 4688
  • -CrowdStrike ProcessRollup2
search:| tstats `security_content_summariesonly` count values(Processes.process_name) as process_name values(Processes.process) as process min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes
WHERE Processes.parent_process_name=crushftpservice.exe
AND
`process_cmd`
OR
`process_powershell`
BY Processes.dest Processes.parent_process Processes.original_file_name
Processes.user Processes.action Processes.parent_process_exec
Processes.parent_process_guid Processes.parent_process_id Processes.parent_process_path
Processes.process_exec Processes.process_guid Processes.process_hash
Processes.process_id Processes.process_integrity_level Processes.process_path
Processes.user_id Processes.vendor_product
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_shell_process_from_crushftp_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.
known_false_positives:No false positives have been identified at this time.
References:
  -https://nvd.nist.gov/vuln/detail/CVE-2025-31161
  -https://www.crushftp.com/crush11wiki/Wiki.jsp?page=Update
  -https://www.huntress.com/blog/crushftp-cve-2025-31161-auth-bypass-and-post-exploitation
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'
analytic_story:['CrushFTP Vulnerabilities']

asset_type:Endpoint

mitre_attack_id:['T1059.001', 'T1059.003', 'T1190', 'T1505']

product:['Splunk Enterprise', 'Splunk Enterprise Security', 'Splunk Cloud']

category:endpoint

security_domain:endpoint

tags:

tests:
 name:'True Positive Test'
 attack_data:
  data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1190/crushftp/windows-sysmon.log
  source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
  sourcetype: XmlWinEventLog
 test_type:'unit'
manual_test:None

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