Detection rules › Splunk

EnableLUA Registry Value Modified (PowerShell)

Group by
_time, host
Source
github.com/anvilogic-forge/armory

Adversaries may bypass UAC mechanisms to elevate process privileges on system. Windows User Account Control (UAC) allows a program to elevate its privileges (tracked as integrity levels ranging from low to high) to perform a task under administrator-level permissions, possibly by prompting the user for confirmation. This use case detects registry modification events or process executions with registry modification commands targeting HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA.

MITRE ATT&CK coverage

References

Event coverage

Rule body yaml

id: '31087.55689'
title: EnableLUA Registry Value Modified
description: Adversaries may bypass UAC mechanisms to elevate process privileges on
  system. Windows User Account Control (UAC) allows a program to elevate its privileges
  (tracked as integrity levels ranging from low to high) to perform a task under administrator-level
  permissions, possibly by prompting the user for confirmation. This use case detects
  registry modification events or process executions with registry modification commands
  targeting HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA.
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_powershell` (TERM(EventCode=4103) OR
  "<EventID>4103<" OR TERM(EventCode=4104) OR "<EventID>4104<") ("Set-Item-Property"
  OR "sp " OR "ADD") "EnableLUA" "SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Policies\\System"
  | table _time, host, user user, process, process_* | bin span=1s | stats values(*)
  as * by _time, host '
techniques:
- privilege-escalation:abuse elevation control mechanism:bypass user account control
technique_id:
- T1548.002
data_category:
- PowerShell logs
references:
- https://attack.mitre.org/techniques/T1548/002/

Stages and Predicates

Stage 1: search

`get_endpoint_data` `get_endpoint_data_powershell` (TERM(EventCode=4103) OR "<EventID>4103<" OR TERM(EventCode=4104) OR "<EventID>4104<") ("Set-Item-Property" OR "sp " OR "ADD") "EnableLUA" "SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Policies\\System"

Stage 2: table

| table _time, host, user user, process, process_*

Stage 3: bucket

| bin span=1s

Stage 4: stats

| stats values(*) as * by _time, host

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
EventCodeeq
  • 4103 corpus 105 (splunk 105)
  • 4104 corpus 268 (splunk 268)

Search terms

Bare-string tokens in the SPL search body. Splunk matches each token against _raw (the untyped raw event text) anywhere it appears, not against a specific field. These don't surface in the Indicators table because they aren't predicates on a known field.

StageTerm
1TERM
1"<EventID>4103<"
1TERM
1"<EventID>4104<"
1"Set-Item-Property"
1"sp "
1"ADD"
1"EnableLUA"
1"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Policies\\System"