Disabling User Account Control via Registry Modificationedit

User Account Control (UAC) can help mitigate the impact of malware on Windows hosts. With UAC, apps and tasks always run in the security context of a non-administrator account, unless an administrator specifically authorizes administrator-level access to the system. This rule identifies registry value changes to bypass User Access Control (UAC) protection.

Rule type: eql

Rule indices:

  • winlogbeat-*
  • logs-endpoint.events.*
  • logs-windows.*

Severity: medium

Risk score: 47

Runs every: 5 minutes

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

Tags:

  • Elastic
  • Host
  • Windows
  • Threat Detection
  • Privilege Escalation

Version: 4 (version history)

Added (Elastic Stack release): 7.12.0

Last modified (Elastic Stack release): 8.2.0

Rule authors: Elastic

Rule license: Elastic License v2

Investigation guideedit

## Config

If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define `event.ingested` and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate `event.ingested` to @timestamp for this rule to work.

Rule queryedit

registry where event.type == "change" and registry.path : (
"HKLM\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Policies\\System\
\EnableLUA", "HKLM\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion
\\Policies\\System\\ConsentPromptBehaviorAdmin", "HKLM\\SOFTWARE
\\Microsoft\\Windows\\CurrentVersion\\Policies\\System\\PromptOnSecure
Desktop" ) and registry.data.strings : ("0", "0x00000000")

Threat mappingedit

Framework: MITRE ATT&CKTM

Rule version historyedit

Version 4 (8.2.0 release)
  • Formatting only
Version 3 (8.1.0 release)
  • Updated query, changed from:

    registry where event.type == "change" and registry.path : (
    "HKLM\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Policies\\System\
    \EnableLUA", "HKLM\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion
    \\Policies\\System\\ConsentPromptBehaviorAdmin", "HKLM\\SOFTWARE
    \\Microsoft\\Windows\\CurrentVersion\\Policies\\System\\PromptOnSecure
    Desktop" ) and registry.data.strings : "0"
Version 2 (7.15.0 release)
  • Formatting only