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Description

As simple as it sounds, this analytic identifies when the native mimikatz.exe binary executes on Windows. It does look for the original file name as well, just in case the binary is renamed. Adversaries sometimes bring in the default binary and run it directly. Benjamin Delpy originally created Mimikatz as a proof of concept to show Microsoft that its authentication protocols were vulnerable to an attack. Instead, he inadvertently created one of the most widely used and downloaded threat actor tools of the past 20 years. Mimikatz is an open-source application that allows users to view and save authentication credentials such as Kerberos tickets.

  • Type: TTP
  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
  • Datamodel: Endpoint
  • Last Updated: 2022-11-16
  • Author: Michael Haag, Splunk
  • ID: a9e0d6d3-9676-4e26-994d-4e0406bb4467

Annotations

ATT&CK

ATT&CK

ID Technique Tactic
T1003 OS Credential Dumping Credential Access
Kill Chain Phase
  • Exploitation
NIST
  • DE.CM
CIS20
  • CIS 10
CVE 


1
2
3
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6



| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where (Processes.process_name=mimikatz.exe OR Processes.original_file_name=mimikatz.exe) by Processes.dest Processes.user Processes.parent_process_name Processes.process_name Processes.original_file_name Processes.process Processes.process_id Processes.parent_process_id 
| `drop_dm_object_name(Processes)` 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `windows_mimikatz_binary_execution_filter`

Macros

The SPL above uses the following Macros:

:information_source: windows_mimikatz_binary_execution_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.dest
  • Processes.user
  • Processes.parent_process_name
  • Processes.parent_process
  • Processes.original_file_name
  • Processes.process_name
  • Processes.process
  • Processes.process_id
  • Processes.parent_process_path
  • Processes.process_path
  • Processes.parent_process_id

How To Implement

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

False positives should be limited as this is directly looking for Mimikatz, the credential dumping utility.

Associated Analytic Story

RBA

Risk Score Impact Confidence Message
100.0 100 100 An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $user$ attempting dump credentials.

: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

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