diff --git a/detections/endpoint/ssa___windows_powersh.yml b/detections/endpoint/ssa___windows_powersh.yml deleted file mode 100644 index 939778867e..0000000000 --- a/detections/endpoint/ssa___windows_powersh.yml +++ /dev/null @@ -1,94 +0,0 @@ -name: Windows Powershell DownloadFile -id: 46440222-81d5-44b1-a376-19dcd70d1b08 -version: 1 -date: '2022-02-11' -author: Jose Hernandez, Michael Haag, Splunk -type: Anomaly -datamodel: -- Endpoint_Processes -description: The following analytic identifies the use of PowerShell downloading a - file using `DownloadFile` method. This particular method is utilized in many different - PowerShell frameworks to download files and output to disk. Identify the source - (IP/domain) and destination file and triage appropriately. If AMSI logging or PowerShell - transaction logs are available, review for further details of the implant. -search: '| from read_ssa_enriched_events() | eval timestamp=parse_long(ucast(map_get(input_event, - "_time"), "string", null)), cmd_line=lower(ucast(map_get(input_event, "process"), - "string", null)), process_name=lower(ucast(map_get(input_event, "process_name"), - "string", null)), process_path=ucast(map_get(input_event, "process_path"), "string", - null), parent_process_name=ucast(map_get(input_event, "parent_process_name"), "string", - null), event_id=ucast(map_get(input_event, "event_id"), "string", null) | where - cmd_line IS NOT NULL AND process_name IS NOT NULL | where process_name="pwsh.exe" - OR process_name="pwsh.exe" OR process_name="sqlps.exe" OR process_name="sqltoolsps.exe" - OR process_name="powershell.exe" OR process_name="powershell_ise.exe" | where (like - (cmd_line, "%downloadfile%")) | eval start_time=timestamp, end_time=timestamp, entities=mvappend(ucast(map_get(input_event, - "dest_user_id"), "string", null), ucast(map_get(input_event, "dest_device_id"), - "string", null)), body=create_map(["event_id", event_id, "cmd_line", cmd_line, "process_name", - process_name, "parent_process_name", parent_process_name, "process_path", process_path]) - | into write_ssa_detected_events();' -how_to_implement: To successfully implement this search you need to be ingesting information - on process that include the name of the process responsible for the changes from - your endpoints into the `Endpoint` datamodel in the `Processes` node. In addition, - confirm the latest CIM App 4.20 or higher is installed and the latest TA for the - endpoint product. -known_false_positives: False positives may be present and filtering will need to occur - by parent process or command line argument. It may be required to modify this query - to an EDR product for more granular coverage. -references: -- https://docs.microsoft.com/en-us/dotnet/api/system.net.webclient.downloadfile?view=net-5.0 -- https://blog.malwarebytes.com/malwarebytes-news/2021/02/lazyscripter-from-empire-to-double-rat/ -- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1059.001/T1059.001.md -tags: - analytic_story: - - Malicious PowerShell - - Ingress Tool Transfer - - Log4Shell CVE-2021-44228 - cis20: - - CIS 8 - confidence: 70 - context: - - Source:Endpoint - - Stage:LateralMovement - dataset: - - https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1059.001/atomic_red_team/downloadfile_windows-security.log - impact: 50 - kill_chain_phases: - - Lateral Movement - message: An instance of $parent_process_name$ spawning $process_name$ was identified - on endpoint $dest$ by user $user$. This behavior identifies the use of DownloadFile - within PowerShell. - mitre_attack_id: - - T1020 - nist: - - PR.PT - - DE.CM - observable: - - name: dest_user_id - type: User - role: - - Victim - - name: dest_device_id - type: Hostname - role: - - Victim - - name: parent_process_name - type: Parent Process - role: - - Parent Process - - name: process_name - type: Process - role: - - Child Process - product: - - Splunk Behavioral Analytics - required_fields: - - _time - - dest_device_id - - process_name - - parent_process_name - - process_path - - dest_user_id - - process - - cmd_line - risk_score: 35 - risk_severity: low - security_domain: endpoint