winword wsh

detections/endpoint/winword_spawning_powershell.yml

@@ -28,6 +28,7 @@ references:
 - https://redcanary.com/threat-detection-report/techniques/powershell/
 - https://attack.mitre.org/techniques/T1566/001/
 - https://app.any.run/tasks/b79fa381-f35c-4b3e-8d02-507e7ee7342f/
+- https://app.any.run/tasks/181ac90b-0898-4631-8701-b778a30610ad/
 tags:
   analytic_story:
   - Spearphishing Attachments

detections/endpoint/winword_spawning_windows_script_host.yml

@@ -0,0 +1,51 @@
+name: Winword Spawning Windows Script Host
+id: 637e1b5c-9be1-11eb-9c32-acde48001122
+version: 1
+date: '2021-04-12'
+author: Michael Haag, Splunk
+type: batch
+datamodel:
+- Endpoint
+description: The following detection identifies Microsoft Winword.exe spawning Windows Script
+  Host - `cscript.exe` or `wscript.exe`. Typically, this is not common behavior and
+  not default with Winword.exe. Winword.exe will generally be found in the following path
+  `C:\Program Files\Microsoft Office\root\Office16` (version will vary). `cscript.exe`
+  or `wscript.exe` default location is `c:\windows\system32\` or c:windows\syswow64\`.
+  `cscript.exe` or `wscript.exe` spawning from Winword.exe is common for a spearphishing
+  attachment and is actively used. Albeit, the command-line executed will most likely
+  be obfuscated and captured via another detection. During triage, review parallel
+  processes and identify any files that may have been written. Review the reputation
+  of the remote destination and block accordingly.
+search: '  | tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
+  as lastTime from datamodel=Endpoint.Processes where Processes.parent_process_name="winword.exe" Processes.process_name IN ("cscript.exe", "wscript.exe") by Processes.dest Processes.user Processes.parent_process Processes.process_name
+  Processes.process Processes.process_id Processes.parent_process_id
+  | `drop_dm_object_name(Processes)` 
+  | `security_content_ctime(firstTime)`
+  | `security_content_ctime(lastTime)` | `winword_spawning_windows_script_host_filter`'
+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.
+known_false_positives: There will be limited false positives and it will be different for every environment. Tune by child process or command-line as needed.
+references:
+  - https://attack.mitre.org/techniques/T1566/001/
+tags:
+  analytic_story:
+  - Spearphishing Attachment
+  dataset: []
+  kill_chain_phases:
+  - Exploitation
+  mitre_attack_id:
+  - T1566.001
+  product:
+  - Splunk Enterprise
+  - Splunk Enterprise Security
+  - Splunk Cloud
+  required_fields:
+  - _time
+  - process_name
+  - process_id
+  - parent_process_name
+  - dest
+  - user
+  - parent_process_id
+  security_domain: endpoint

tests/endpoint/winword_spawning_windows_script_host.test.yml

@@ -0,0 +1,12 @@
+name: Winword Spawning Windows Script Host Unit Test
+tests:
+- name: Winword Spawning Windows Script Host
+  file: endpoint/winword_spawning_windows_script_host.yml
+  pass_condition: '| stats count | where count > 0'
+  earliest_time: '-24h'
+  latest_time: 'now'
+  attack_data:
+  - file_name: windows-sysmon.log
+    data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1566.001/macro/windows-sysmon.log
+    source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
+    sourcetype: xmlwineventlog