From 2a32bc9694a3949cffbf9e3c856f2bf1a8a10781 Mon Sep 17 00:00:00 2001
From: mvelazco <mauricio.velazco@gmail.com>
Date: Fri, 17 Mar 2023 14:17:07 -0400
Subject: [PATCH] adding new detection

---
 .../windows_findstr_gpp_discovery.yml         | 75 +++++++++++++++++++
 .../windows_powershell_gpp_discovery.yml      |  1 +
 .../windows_findstr_gpp_discovery.test.yml    | 12 +++
 3 files changed, 88 insertions(+)
 create mode 100644 detections/endpoint/windows_findstr_gpp_discovery.yml
 create mode 100644 tests/endpoint/windows_findstr_gpp_discovery.test.yml

diff --git a/detections/endpoint/windows_findstr_gpp_discovery.yml b/detections/endpoint/windows_findstr_gpp_discovery.yml
new file mode 100644
index 0000000000..32b06dfee3
--- /dev/null
+++ b/detections/endpoint/windows_findstr_gpp_discovery.yml
@@ -0,0 +1,75 @@
+name: Windows Findstr GPP Discovery
+id: 1631ac2d-f2a9-42fa-8a59-d6e210d472f5
+version: 1
+date: '2023-03-16'
+author: Mauricio Velazco, Splunk
+type: TTP
+datamodel: []
+description: UPDATE_DESCRIPTION
+search: ' | tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
+  as lastTime from datamodel=Endpoint.Processes where (Processes.process_name=findstr.exe AND Processes.process=*sysvol* AND Processes.process=*cpassword*)
+  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)`
+  | `windows_findstr_gpp_discovery_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. In addition,
+  confirm the latest CIM App 4.20 or higher is installed and the latest TA for the
+  endpoint product.
+known_false_positives: Administrators may leverage findstr to find passwords in GPO to validate exposure. Filter as needed.
+references:
+- https://pentestlab.blog/2017/03/20/group-policy-preferences/
+- https://adsecurity.org/?p=2288 
+- https://www.hackingarticles.in/credential-dumping-group-policy-preferences-gpp/
+- https://attack.mitre.org/techniques/T1552/006/
+tags:
+  analytic_story:
+  - Active Directory Privilege Escalation
+  asset_type: Endpoint
+  cis20:
+  - CIS 3
+  - CIS 5
+  - CIS 16
+  confidence: 80
+  context:
+  - Source:Endpoint
+  - Stage:Privilege Escalation
+  dataset:
+  - https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1552.006/findstr_gpp_discovery/windows-security.log
+  impact: 70
+  kill_chain_phases:
+  - Exploitation
+  message: Findstr was executed to discover GPP credentials on $dest$
+  mitre_attack_id:
+  - T1552
+  - T1552.006
+  nist:
+  - DE.CM
+  observable:
+  - name: dest
+    type: Hostname
+    role:
+    - Victim
+  - name: user
+    type: User
+    role:
+    - Victim
+  product:
+  - Splunk Enterprise
+  - Splunk Enterprise Security
+  - Splunk Cloud
+  required_fields:
+  - _time
+  - Processes.user
+  - Processes.dest
+  - Processes.process_name
+  - Processes.process
+  - Processes.dest
+  - Processes.user
+  - Processes.parent_process_name
+  - Processes.process_name
+  - Processes.process_id 
+  - Processes.parent_process_id
+  - Processes.original_file_name 
+  risk_score: 56
+  security_domain: endpoint
diff --git a/detections/endpoint/windows_powershell_gpp_discovery.yml b/detections/endpoint/windows_powershell_gpp_discovery.yml
index 44c4d1151d..dba0d3d7a6 100644
--- a/detections/endpoint/windows_powershell_gpp_discovery.yml
+++ b/detections/endpoint/windows_powershell_gpp_discovery.yml
@@ -18,6 +18,7 @@ references:
 - https://pentestlab.blog/2017/03/20/group-policy-preferences/
 - https://adsecurity.org/?p=2288 
 - https://www.hackingarticles.in/credential-dumping-group-policy-preferences-gpp/
+- https://attack.mitre.org/techniques/T1552/006/
 tags:
   analytic_story:
   - Active Directory Privilege Escalation
diff --git a/tests/endpoint/windows_findstr_gpp_discovery.test.yml b/tests/endpoint/windows_findstr_gpp_discovery.test.yml
new file mode 100644
index 0000000000..3805dee99c
--- /dev/null
+++ b/tests/endpoint/windows_findstr_gpp_discovery.test.yml
@@ -0,0 +1,12 @@
+name: Windows Findstr GPP Discovery Unit Test
+tests:
+- name: Windows Findstr GPP Discovery
+  file: endpoint/windows_findstr_gpp_discovery.yml
+  pass_condition: '| stats count | where count > 0'
+  earliest_time: -24h
+  latest_time: now
+  attack_data:
+  - file_name: windows-security.log
+    data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1552.006/findstr_gpp_discovery/windows-security.log
+    source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
+    sourcetype: xmlwineventlog