Name:Windows Powershell History File Deletion id:f1369394-48e1-4327-bf6d-14377f4b8687 version:7 date:None author:Teoderick Contreras, Splunk status:production type:Anomaly Description:The following analytic detects the usage of PowerShell to delete its command history file, which may indicate an attempt to evade detection by removing evidence of executed commands. PowerShell stores command history in ConsoleHost_history.txt under the user’s profile directory. Adversaries or malicious scripts may delete this file using Remove-Item, del, or similar commands. This detection focuses on file deletion events targeting the history file, correlating them with recent PowerShell activity. While legitimate users may occasionally clear history, frequent or automated deletions should be investigated for potential defense evasion or post-exploitation cleanup activities. Data_source:
| stats count min(_time) as firstTime max(_time) as lastTime BY dest signature signature_id user_id vendor_product Guid Opcode Name Path ProcessID ScriptBlockId ScriptBlockText
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:administrators may execute this command that may cause some false positive. References: -https://www.cisa.gov/news-events/cybersecurity-advisories/aa25-071a 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:['Medusa Ransomware']
