Name:7zip CommandLine To SMB Share Path id:01d29b48-ff6f-11eb-b81e-acde48001123 version:4 date:2024-11-26 author:Teoderick Contreras, Splunk status:production type:Hunting Description:The following analytic detects the execution of 7z or 7za processes with command lines pointing to SMB network shares. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. This activity is significant as it may indicate an attempt to archive and exfiltrate sensitive files to a network share, a technique observed in CONTI LEAK tools. If confirmed malicious, this behavior could lead to data exfiltration, compromising sensitive information and potentially aiding further attacks. 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.process_name ="7z.exe" OR Processes.process_name = "7za.exe" OR Processes.process_name = "7zr.exe" OR Processes.original_file_name = "7z.exe" OR Processes.original_file_name = "7za.exe" OR Processes.original_file_name = "7zr.exe") AND (Processes.process="*\\C$\\*" OR Processes.process="*\\Admin$\\*" OR Processes.process="*\\IPC$\\*") by Processes.original_file_name Processes.parent_process_name Processes.parent_process Processes.process_name Processes.process Processes.parent_process_id Processes.process_id Processes.dest Processes.user | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `7zip_commandline_to_smb_share_path_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 References: -https://threadreaderapp.com/thread/1423361119926816776.html drilldown_searches:
: tags: analytic_story: - 'Ransomware' asset_type:Endpoint confidence:50 impact:50 message:archive process $process_name$ with suspicious cmdline $process$ in host $dest$ mitre_attack_id: - 'T1560.001' - 'T1560' observable: name:'dest' type:'Endpoint' - role: - 'Victim' name:'user' type:'User' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'Processes.dest' - 'Processes.user' - 'Processes.parent_process' - 'Processes.parent_process_name' - 'Processes.process_name' - 'Processes.process' - 'Processes.process_id' - 'Processes.parent_process_id' risk_score:25 security_domain:endpoint
