Detection rules › Splunk

Windows Impair Defense Disable Win Defender Gen reports

Status
production
Severity
medium
Group by
TargetObject, computer_name, details, event_type, process_guid, process_id, registry_hive, registry_path, registry_status, registry_value_name, registry_value_type, user, vendor_product
Author
Teoderick Contreras, Splunk
Source
github.com/splunk/security_content

The following analytic detects modifications in the Windows registry to disable Windows Defender generic reports. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the "DisableGenericRePorts" registry value. This activity is significant as it can prevent the transmission of error reports to Microsoft's Windows Error Reporting service, potentially hiding malicious activities. If confirmed malicious, this action could allow attackers to bypass Windows Defender detections, reducing the visibility of their activities and increasing the risk of undetected system compromise.

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

TacticTechniques
Defense Impairment

Telemetry coverage

Rule body

name: Windows Impair Defense Disable Win Defender Gen reports
id: 93f114f6-cb1e-419b-ac3f-9e11a3045e70
version: 11
creation_date: '2024-01-29'
modification_date: '2026-05-13'
author: Teoderick Contreras, Splunk
status: production
type: TTP
description: The following analytic detects modifications in the Windows registry to disable Windows Defender generic reports. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the "DisableGenericRePorts" registry value. This activity is significant as it can prevent the transmission of error reports to Microsoft's Windows Error Reporting service, potentially hiding malicious activities. If confirmed malicious, this action could allow attackers to bypass Windows Defender detections, reducing the visibility of their activities and increasing the risk of undetected system compromise.
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\\Reporting\\DisableGenericRePorts" Registry.registry_value_data="0x00000001" 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_win_defender_gen_reports_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 DisableGenericRePorts registry is set to enable on $dest$.
    entity:
        field: dest
        type: system
        score: 50
analytic_story:
    - Windows Defense Evasion Tactics
    - Windows Registry Abuse
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\\Reporting\\DisableGenericRePorts" Registry.registry_value_data="0x00000001" 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_win_defender_gen_reports_filter`

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Registry.registry_patheq
  • "*\\Windows Defender\\Reporting\\DisableGenericRePorts"
field:"registry_path" kind:eq
Registry.registry_value_dataeq
  • "0x00000001" corpus 61 (splunk 52, elastic 9)
field:"Details" kind:eq