Name:Suspicious writes to windows Recycle Bin id:b5541828-8ffd-4070-9d95-b3da4de924cb version:7 date:2025-04-22 author:Rico Valdez, Splunk status:production type:TTP Description:The following analytic detects when a process other than explorer.exe writes to the Windows Recycle Bin. It leverages the Endpoint.Filesystem and Endpoint.Processes data models in Splunk to identify any process writing to the "*$Recycle.Bin*" file path, excluding explorer.exe. This activity is significant because it may indicate an attacker attempting to hide their actions, potentially leading to data theft, ransomware, or other malicious outcomes. If confirmed malicious, this behavior could allow an attacker to persist in the environment and evade detection by security tools. Data_source:
-Sysmon EventID 1 AND Sysmon EventID 11
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime values(Filesystem.file_path) as file_path values(Filesystem.file_name) as file_name FROM datamodel=Endpoint.Filesystem where Filesystem.file_path = "*$Recycle.Bin*" by Filesystem.process_name Filesystem.process_id Filesystem.dest | `drop_dm_object_name("Filesystem")` | join process_id [| tstats `security_content_summariesonly` values(Processes.user) as user values(Processes.process_name) as process_name values(Processes.parent_process_name) as parent_process_name FROM datamodel=Endpoint.Processes where Processes.process_name != "explorer.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")` | table user process_name process_id dest] | `suspicious_writes_to_windows_recycle_bin_filter`
how_to_implement:To successfully implement this search you need to be ingesting information on filesystem and process logs responsible for the changes from your endpoints into the `Endpoint` datamodel in the `Processes` and `Filesystem` nodes. known_false_positives:Because the Recycle Bin is a hidden folder in modern versions of Windows, it would be unusual for a process other than explorer.exe to write to it. Incidents should be investigated as appropriate. References: 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: - 'Collection and Staging' - 'PlugX' asset_type:Windows mitre_attack_id: - 'T1036' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' security_domain:endpoint
