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Description

The following analytic detects the use of the Certipy tool to enumerate Active Directory Certificate Services (AD CS) environments by identifying unique file modifications. It leverages endpoint process and filesystem data to spot the creation of files with specific names or extensions associated with Certipy's information gathering and exfiltration activities. This activity is significant as it indicates potential reconnaissance and data exfiltration efforts by an attacker. If confirmed malicious, this could lead to unauthorized access to sensitive AD CS information, enabling further attacks or privilege escalation within the network.

  • Type: TTP
  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
  • Datamodel: Endpoint
  • Last Updated: 2024-05-27
  • Author: Steven Dick
  • ID: 7e3df743-b1d8-4631-8fa8-bd5819688876

Annotations

ATT&CK

ATT&CK

ID Technique Tactic
T1649 Steal or Forge Authentication Certificates Credential Access
T1560 Archive Collected Data Collection
Kill Chain Phase
  • Exploitation
NIST
  • DE.CM
CIS20
  • CIS 10
CVE 


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| tstats `security_content_summariesonly` count min(_time) AS firstTime max(_time) AS lastTime values(Processes.process_current_directory) as process_current_directory FROM datamodel=Endpoint.Processes where Processes.action="allowed" BY _time span=1h Processes.user Processes.dest Processes.process_id Processes.process_name Processes.process Processes.process_path Processes.parent_process_name Processes.parent_process Processes.process_guid Processes.action 
|`drop_dm_object_name(Processes)` 
| join max=0 dest process_guid [
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Filesystem where Filesystem.file_name IN ("*_certipy.zip", "*_certipy.txt", "*_certipy.json", "*.ccache") by Filesystem.file_create_time Filesystem.process_id Filesystem.process_guid Filesystem.file_name Filesystem.file_path Filesystem.dest 
| `drop_dm_object_name(Filesystem)` ] 
| fields firstTime lastTime user dest file_create_time file_name file_path parent_process_name parent_process process_name process_path process_current_directory process process_guid process_id 
| where isnotnull(file_name) 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `detect_certipy_file_modifications_filter`

Macros

The SPL above uses the following Macros:

:information_source: detect_certipy_file_modifications_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Required fields

List of fields required to use this analytic.

  • _time
  • Processes.user
  • Processes.dest
  • Processes.process_id
  • Processes.process_name
  • Processes.process
  • Processes.process_path
  • Processes.parent_process_name
  • Processes.parent_process
  • Processes.process_guid
  • Processes.action
  • Filesystem.file_create_time
  • Filesystem.process_id
  • Filesystem.process_guid
  • Filesystem.file_name
  • Filesystem.file_path
  • Filesystem.dest

How To Implement

To successfully implement this search, you need to be ingesting logs with the process name, parent process, and command-line executions from your endpoints as well as file creation or deletion events.

Known False Positives

Unknown

Associated Analytic Story

RBA

Risk Score Impact Confidence Message
45.0 50 90 Suspicious files $file_name$ related to Certipy detected on $dest$

:information_source: The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

Reference

Test Dataset

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

source | version: 2