Name:Suspicious Copy on System32 id:ce633e56-25b2-11ec-9e76-acde48001122 version:11 date:2025-06-17 author:Teoderick Contreras, Nasreddine Bencherchali, Splunk status:production type:Anomaly Description:The following analytic detects potentially suspicious file copy operations targeting the
System32 or SysWow64 directories as source, often indicative of malicious activity.
It leverages data from Endpoint Detection and Response (EDR) agents,
focusing on activity initiated by command-line tools like cmd.exe or PowerShell.
This behavior is significant as it may indicate an attempt to evade defenses by copying
an existing binary from the system directory and renaming it.
If confirmed malicious, this activity could allow an attacker to execute
code undetected and potentially leading to system compromise or further lateral movement
within the network.
Data_source:
-Sysmon EventID 1
-Windows Event Log Security 4688
-CrowdStrike ProcessRollup2
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.parent_process_name IN ( "cmd.exe", "powershell_ise.exe", "powershell.exe", "pwsh.exe", "sqlps.exe", "sqltoolsps.exe" ) `process_copy` Processes.process IN ( "* \"C:\\Windows\\System32\\*", "* \'C:\\Windows\\System32\\*", "* C:\\Windows\\System32\\*", "* \"C:\\Windows\\SysWow64\\*", "* \'C:\\Windows\\SysWow64\\*", "* C:\\Windows\\SysWow64\\*" ) 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)` | `suspicious_copy_on_system32_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:Copying files from System directories can happen for multiple admin reasons, allbeit rare without approval. Apply additional filters where needed. References: -https://www.hybrid-analysis.com/sample/8da5b75b6380a41eee3a399c43dfe0d99eeefaa1fd21027a07b1ecaa4cd96fdd?environmentId=120 -https://www.microsoft.com/en-us/security/blog/2023/05/24/volt-typhoon-targets-us-critical-infrastructure-with-living-off-the-land-techniques/ drilldown_searches: name:'View the detection results for - "$dest$" and "$user$"' search:'%original_detection_search% | search dest = "$dest$" user = "$user$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$dest$" and "$user$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$", "$user$") 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: - 'Qakbot' - 'Sandworm Tools' - 'IcedID' - 'Volt Typhoon' - 'AsyncRAT' - 'Unusual Processes' - 'Compromised Windows Host' - 'Water Gamayun' asset_type:Endpoint mitre_attack_id: - 'T1036.003' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' security_domain:endpoint
