Name:Detect Renamed WinRAR id:1b7bfb2c-b8e6-11eb-99ac-acde48001122 version:6 date:2024-10-17 author:Michael Haag, Splunk status:production type:Hunting Description:The following analytic identifies instances where `WinRAR.exe` has been renamed and executed. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and original file names within the Endpoint data model. This activity is significant because renaming executables is a common tactic used by attackers to evade detection. If confirmed malicious, this could indicate an attempt to bypass security controls, potentially leading to unauthorized data extraction or further system compromise. 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.original_file_name=WinRAR.exe (Processes.process_name!=rar.exe OR Processes.process_name!=winrar.exe) by Processes.dest Processes.user Processes.parent_process_name Processes.process_name Processes.process Processes.process_id Processes.parent_process_id Processes.original_file_name | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `detect_renamed_winrar_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. It is possible third party applications use renamed instances of WinRAR. References: -https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1560.001/T1560.001.md drilldown_searches:
: tags: analytic_story: - 'Collection and Staging' - 'CISA AA22-277A' asset_type:Endpoint confidence:90 impact:30 message:The following $process_name$ has been identified as renamed, spawning from $parent_process_name$ on $dest$ by $user$. mitre_attack_id: - 'T1560.001' - 'T1560' observable: name:'user' type:'User' - role: - 'Victim' name:'dest' type:'Hostname' - role: - 'Victim' name:'parent_process_name' type:'Process' - role: - 'Attacker' name:'process_name' type:'Process' - role: - 'Attacker' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'Processes.dest' - 'Processes.user' - 'Processes.parent_process_name' - 'Processes.parent_process' - 'Processes.original_file_name' - 'Processes.process_name' - 'Processes.process' - 'Processes.process_id' - 'Processes.parent_process_path' - 'Processes.process_path' - 'Processes.parent_process_id' risk_score:27 security_domain:endpoint
