Detection rules › Splunk
Windows Impair Defense Disable Controlled Folder Access
The following analytic detects a modification in the Windows registry that disables the Windows Defender Controlled Folder Access feature. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the EnableControlledFolderAccess registry setting. This activity is significant because Controlled Folder Access is designed to protect critical folders from unauthorized access, including ransomware attacks. If this activity is confirmed malicious, it could allow attackers to bypass a key security feature, potentially leading to unauthorized access or modification of sensitive files.
Known false positives
- It is unusual to turn this feature off a Windows system since it is a default security control, although it is not rare for some policies to disable it. Although no false positives have been identified, use the provided filter macro to tune the search.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Defense Impairment |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 13: RegistryEvent (Value Set) |
Rule body
name: Windows Impair Defense Disable Controlled Folder Access
id: 3032741c-d6fc-4c69-8988-be8043d6478c
version: 11
creation_date: '2024-01-30'
modification_date: '2026-05-13'
author: Teoderick Contreras, Splunk
status: production
type: TTP
description: The following analytic detects a modification in the Windows registry that disables the Windows Defender Controlled Folder Access feature. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the EnableControlledFolderAccess registry setting. This activity is significant because Controlled Folder Access is designed to protect critical folders from unauthorized access, including ransomware attacks. If this activity is confirmed malicious, it could allow attackers to bypass a key security feature, potentially leading to unauthorized access or modification of sensitive files.
data_source:
- Sysmon EventID 13
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Registry where Registry.registry_path= "*\\Windows Defender\\Windows Defender Exploit Guard\\Controlled Folder Access\\EnableControlledFolderAccess" Registry.registry_value_data="0x00000000" by Registry.action Registry.dest Registry.process_guid Registry.process_id Registry.registry_hive Registry.registry_path Registry.registry_key_name Registry.registry_value_data Registry.registry_value_name Registry.registry_value_type Registry.status Registry.user Registry.vendor_product | `drop_dm_object_name(Registry)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `windows_impair_defense_disable_controlled_folder_access_filter`'
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 `Registry` node.
known_false_positives: It is unusual to turn this feature off a Windows system since it is a default security control, although it is not rare for some policies to disable it. Although no false positives have been identified, use the provided filter macro to tune the search.
references:
- https://x.com/malmoeb/status/1742604217989415386?s=20
- https://github.com/undergroundwires/privacy.sexy
finding:
title: Windows Defender ControlledFolderAccess feature set to disable on $dest$.
entity:
field: dest
type: system
score: 50
analytic_story:
- Windows Defense Evasion Tactics
- Windows Registry Abuse
- BlankGrabber Stealer
asset_type: Endpoint
mitre_attack_id:
- T1685
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
category: endpoint
security_domain: endpoint
Stages and Predicates
Stage 1: tstats
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Registry where Registry.registry_path= "*\\Windows Defender\\Windows Defender Exploit Guard\\Controlled Folder Access\\EnableControlledFolderAccess" Registry.registry_value_data="0x00000000" by Registry.action Registry.dest Registry.process_guid Registry.process_id Registry.registry_hive Registry.registry_path Registry.registry_key_name Registry.registry_value_data Registry.registry_value_name Registry.registry_value_type Registry.status Registry.user Registry.vendor_product
Stage 2: search
| `drop_dm_object_name(Registry)`
Stage 3: search
| `security_content_ctime(firstTime)`
Stage 4: search
| `security_content_ctime(lastTime)`
Stage 5: search
| `windows_impair_defense_disable_controlled_folder_access_filter`
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
Registry.registry_path | eq |
| field:"registry_path" kind:eq |
Registry.registry_value_data | eq |
| field:"Details" kind:eq |