Detection rules › Splunk

Disabling Remote User Account Control

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
David Dorsey, Patrick Bareiss, Splunk
Source
github.com/splunk/security_content

The following analytic identifies modifications to the registry key that controls the enforcement of Windows User Account Control (UAC). It detects changes to the registry path HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA where the value is set to 0x00000000. This activity is significant because disabling UAC can allow unauthorized changes to the system without user consent, potentially leading to privilege escalation. If confirmed malicious, an attacker could gain elevated privileges, making it easier to execute further attacks or maintain persistence within the environment.

MITRE ATT&CK coverage

Event coverage

ProviderEventTitle
SysmonEvent ID 13RegistryEvent (Value Set)

Rule body splunk

name: Disabling Remote User Account Control
id: bbc644bc-37df-4e1a-9c88-ec9a53e2038c
version: 14
creation_date: '2020-04-29'
modification_date: '2026-05-13'
author: David Dorsey, Patrick Bareiss, Splunk
status: production
type: TTP
description: The following analytic identifies modifications to the registry key that controls the enforcement of Windows User Account Control (UAC). It detects changes to the registry path `HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA` where the value is set to `0x00000000`. This activity is significant because disabling UAC can allow unauthorized changes to the system without user consent, potentially leading to privilege escalation. If confirmed malicious, an attacker could gain elevated privileges, making it easier to execute further attacks or maintain persistence within the environment.
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=*\\Microsoft\\Windows\\CurrentVersion\\Policies\\System\\EnableLUA* 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)` | `disabling_remote_user_account_control_filter`'
how_to_implement: To successfully implement this search, you must be ingesting data that records registry activity from your hosts to populate the endpoint data model in the registry node. This is typically populated via endpoint detection-and-response product, such as Carbon Black, or via other endpoint data sources, such as Sysmon. The data used for this search is typically generated via logs that report registry modifications.
known_false_positives: This registry key may be modified via administrators to implement a change in system policy. This type of change should be a very rare occurrence.
references: []
drilldown_searches:
    - name: View the detection results for - "$user$" and "$dest$"
      search: '%original_detection_search% | search  user = "$user$" dest = "$dest$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$user$" and "$dest$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$", "$dest$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: 7d
      latest_offset: "0"
finding:
    title: The Windows registry keys that control the enforcement of Windows User Account Control (UAC) were modified on $dest$ by $user$.
    entity:
        field: user
        type: user
        score: 50
intermediate_findings:
    entities:
        - field: dest
          type: system
          score: 50
          message: The Windows registry keys that control the enforcement of Windows User Account Control (UAC) were modified on $dest$ by $user$.
analytic_story:
    - Windows Defense Evasion Tactics
    - Suspicious Windows Registry Activities
    - Remcos
    - Windows Registry Abuse
    - Azorult
    - AgentTesla
asset_type: Endpoint
mitre_attack_id:
    - T1548.002
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1548.002/atomic_red_team/windows-sysmon.log
          source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
          sourcetype: XmlWinEventLog
      test_type: unit

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=*\\Microsoft\\Windows\\CurrentVersion\\Policies\\System\\EnableLUA* 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

| `disabling_remote_user_account_control_filter`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
Registry.registry_patheq
  • "*\\\\Microsoft\\\\Windows\\\\CurrentVersion\\\\Policies\\\\System\\\\EnableLUA*"
Registry.registry_value_dataeq
  • "0x00000000" corpus 43 (splunk 35, elastic 8)