Detection: Detect Certify Command Line Arguments

Description

The following analytic detects the use of Certify or Certipy tools to enumerate Active Directory Certificate Services (AD CS) environments. It leverages Endpoint Detection and Response (EDR) data, focusing on specific command-line arguments associated with these tools. This activity is significant because it indicates potential reconnaissance or exploitation attempts targeting AD CS, which could lead to unauthorized access or privilege escalation. If confirmed malicious, attackers could gain insights into the AD CS infrastructure, potentially compromising sensitive certificates and escalating their privileges within the network.

Search

1
2| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process IN ("* find *","* auth *","* request *","* req *","* download *",) AND Processes.process IN ("* /vulnerable*","* /enrolleeSuppliesSubject *","* /json /outfile*","* /ca*", "* -username *","* -u *") by Processes.dest Processes.user Processes.parent_process Processes.process_name Processes.process Processes.process_id Processes.parent_process_id 
3| `drop_dm_object_name(Processes)` 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)`
6| `detect_certify_command_line_arguments_filter`

Data Source

Name	Platform	Sourcetype	Source
CrowdStrike ProcessRollup2	N/A	'crowdstrike:events:sensor'	'crowdstrike'
Sysmon EventID 1	Windows	'xmlwineventlog'	'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'
Windows Event Log Security 4688	Windows	'xmlwineventlog'	'XmlWinEventLog:Security'

Macros Used

Annotations

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Implementation

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

Associated Analytic Story

• Compromised Windows Host

• Ingress Tool Transfer

• Windows Certificate Services

Risk Based Analytics (RBA)

References

• https://github.com/GhostPack/Certify

• https://github.com/ly4k/Certipy

• https://specterops.io/wp-content/uploads/sites/3/2022/06/Certified_Pre-Owned.pdf

Detection Testing

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: GitHub | Version: 4