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Description

The following analytic detects the creation or deletion of Windows shares using the net.exe command. It leverages Endpoint Detection and Response (EDR) data to identify processes involving net.exe with actions related to share management. This activity is significant because it may indicate an attacker attempting to manipulate network shares for malicious purposes, such as data exfiltration, malware distribution, or establishing persistence. If confirmed malicious, this activity could lead to unauthorized access to sensitive information, service disruption, or malware introduction. Immediate investigation is required to determine the intent and mitigate potential threats.

  • Type: TTP
  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
  • Datamodel: Endpoint
  • Last Updated: 2024-05-26
  • Author: Bhavin Patel, Splunk
  • ID: 743a322c-9a68-4a0f-9c17-85d9cce2a27c

Annotations

ATT&CK

ATT&CK

ID Technique Tactic
T1070 Indicator Removal Defense Evasion
T1070.005 Network Share Connection Removal Defense Evasion
Kill Chain Phase
  • Exploitation
NIST
  • DE.CM
CIS20
  • CIS 10
CVE 


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| tstats `security_content_summariesonly` count values(Processes.user) as user values(Processes.parent_process) as parent_process min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where `process_net` by Processes.process Processes.process_name  Processes.parent_process_name Processes.original_file_name Processes.dest 
| `drop_dm_object_name(Processes)` 
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)` 
| search process=*share* 
| `create_or_delete_windows_shares_using_net_exe_filter`

Macros

The SPL above uses the following Macros:

:information_source: create_or_delete_windows_shares_using_net_exe_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

Administrators often leverage net.exe to create or delete network shares. You should verify that the activity was intentional and is legitimate.

Associated Analytic Story

RBA

Risk Score Impact Confidence Message
25.0 50 50 An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $user$ enumerating Windows file shares.

: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: 7