Try in Splunk Security Cloud

Description

This search is to detect a modification of file or directory permission using takeown.exe windows app. This technique was seen in some ransomware that take the ownership of a folder or files to encrypt or delete it.

  • Type: TTP
  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
  • Datamodel: Endpoint- Datasource: Splunk Add-on for Sysmon
  • Last Updated: 2021-06-10
  • Author: Teoderick Contreras, Splunk
  • ID: fa7ca5c6-c9d8-11eb-bce9-acde48001122

Annotations

ATT&CK
ID Technique Tactic
T1222 File and Directory Permissions Modification Defense Evasion
Kill Chain Phase
  • Exploitation
NIST
CIS20
CVE 
1
2
3
4
5
6

| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_name = "takeown.exe" Processes.process = "*/f*" by Processes.parent_process_name Processes.parent_process Processes.process_name Processes.process Processes.dest Processes.user Processes.process_id Processes.process_guid 
| `drop_dm_object_name(Processes)` 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `permission_modification_using_takeown_app_filter`

Macros

The SPL above uses the following Macros:

Note that permission_modification_using_takeown_app_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Required field

  • _time
  • Processes.parent_process_name
  • Processes.parent_process
  • Processes.process_name
  • Processes.process
  • Processes.dest
  • Processes.user
  • Processes.process_id
  • Processes.process_guid

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. If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA.

Known False Positives

takeown.exe is a normal windows application that may used by network operator.

Associated Analytic story

RBA

Risk Score Impact Confidence Message
56.0 70 80 A suspicious of execution of $process_name$ with process id $process_id$ and commandline $process$ to modify permission of directory or files in host $dest$

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: 1