mirror of
https://github.com/splunk/security_content
synced 2026-06-08 17:32:49 +00:00
Rod Soto
82 lines
2.7 KiB
YAML
82 lines
2.7 KiB
YAML
name: Malicious PowerShell Process With Obfuscation Techniques
|
|
id: cde75cf6-3c7a-4dd6-af01-27cdb4511fd4
|
|
version: 5
|
|
date: '2021-01-19'
|
|
author: David Dorsey, Splunk
|
|
type: TTP
|
|
datamodel:
|
|
- Endpoint
|
|
description: This search looks for PowerShell processes launched with arguments that
|
|
have characters indicative of obfuscation on the command-line.
|
|
search: '| tstats `security_content_summariesonly` count values(Processes.process)
|
|
as process values(Processes.parent_process) as parent_process min(_time) as firstTime
|
|
max(_time) as lastTime from datamodel=Endpoint.Processes where `process_powershell`
|
|
by Processes.user Processes.process_name Processes.original_file_name Processes.parent_process_name
|
|
Processes.dest Processes.process | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)`|
|
|
`security_content_ctime(lastTime)`| eval num_obfuscation = (mvcount(split(process,"`"))-1)
|
|
+ (mvcount(split(process, "^"))-1) + (mvcount(split(process, "''"))-1) | `malicious_powershell_process_with_obfuscation_techniques_filter`
|
|
| search num_obfuscation > 10 '
|
|
how_to_implement: To successfully implement this search you need to be ingesting information
|
|
on process that include the name of the process responsible for the changes from
|
|
your endpoints into the `Endpoint` datamodel in the `Processes` node. In addition,
|
|
confirm the latest CIM App 4.20 or higher is installed and the latest TA for the
|
|
endpoint product.
|
|
known_false_positives: These characters might be legitimately on the command-line,
|
|
but it is not common.
|
|
references: []
|
|
tags:
|
|
analytic_story:
|
|
- Hermetic Wiper
|
|
- Malicious PowerShell
|
|
asset_type: Endpoint
|
|
cis20:
|
|
- CIS 3
|
|
- CIS 7
|
|
- CIS 8
|
|
confidence: 60
|
|
context:
|
|
- Source:Endpoint
|
|
- Stage:Initial Access
|
|
- Stage:Execution
|
|
- Stage:Defense Evasion
|
|
dataset:
|
|
- https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1059.001/obfuscated_powershell/windows-sysmon.log
|
|
impact: 70
|
|
kill_chain_phases:
|
|
- Command & Control
|
|
- Actions on Objectives
|
|
message: Powershell.exe running with potential obfuscated arguments on $dest$
|
|
mitre_attack_id:
|
|
- T1059
|
|
- T1059.001
|
|
nist:
|
|
- PR.PT
|
|
- DE.CM
|
|
- PR.IP
|
|
observable:
|
|
- name: dest
|
|
type: Endpoint
|
|
role:
|
|
- Victim
|
|
product:
|
|
- Splunk Enterprise
|
|
- Splunk Enterprise Security
|
|
- Splunk Cloud
|
|
required_fields:
|
|
- _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
|
|
risk_score: 42
|
|
security_domain: endpoint
|
|
supported_tas:
|
|
- Splunk_TA_microsoft_sysmon
|