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splunk-security_content/dev/endpoint/windows_dism_remove_defender.yml
2023-01-20 13:24:15 +01:00

74 lines
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YAML

name: Windows DISM Remove Defender
id: 8567da9e-47f0-11ec-99a9-acde48001122
version: 1
date: '2021-11-17'
author: Michael Haag, Splunk
status: production
type: TTP
description: The following analytic identifies the use of the Windows Disk Image Utility,
`dism.exe`, to remove Windows Defender. Adversaries may use `dism.exe` to disable
Defender before completing their objective.
data_source:
- Sysmon Event ID 1
search:
selection1:
Image|endswith: dism.exe
selection2:
CommandLine: '*/disable-feature*'
selection3:
CommandLine: '*/online*'
selection4:
CommandLine: '*Windows-Defender*'
selection5:
CommandLine: '*/remove*'
condition: selection1 and selection2 and selection3 and selection4 and selection5
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: Some legitimate administrative tools leverage `dism.exe` to
manipulate packages and features of the operating system. Filter as needed.
references:
- https://thedfirreport.com/2020/11/23/pysa-mespinoza-ransomware/
tags:
analytic_story:
- Windows Defense Evasion Tactics
asset_type: Endpoint
confidence: 100
impact: 80
message: An instance of $parent_process_name$ spawning $process_name$ was identified
on endpoint $dest$ by user $user$ attempting to disable Windows Defender.
mitre_attack_id:
- T1562.001
- T1562
observable:
- name: user
type: User
role:
- Victim
- name: dest
type: Hostname
role:
- Victim
- name: parent_process_name
type: Process
role:
- Parent Process
- name: process_name
type: Process
role:
- Child Process
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
risk_score: 80
security_domain: access
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1562.001/atomic_red_team/windows-sysmon_dism.log
source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
sourcetype: xmlwineventlog