Network-Level Authentication (NLA) Disabled

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Network-Level Authentication (NLA) Disabled

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Identifies the attempt to disable Network-Level Authentication (NLA) via registry modification. Network Level Authentication (NLA) is a feature on Windows that provides an extra layer of security for Remote Desktop (RDP) connections, as it requires users to authenticate before allowing a full RDP session. Attackers can disable NLA to enable persistence methods that require access to the Windows sign-in screen without authenticating, such as Accessibility Features persistence methods, like Sticky Keys.

Rule type: eql

Rule indices:

  • logs-endpoint.events.registry-*
  • endgame-*
  • logs-m365_defender.event-*
  • logs-sentinel_one_cloud_funnel.*
  • logs-windows.sysmon_operational-*

Severity: low

Risk score: 21

Runs every: 5m

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

Maximum alerts per execution: 100

References:

Tags:

  • Domain: Endpoint
  • OS: Windows
  • Use Case: Threat Detection
  • Tactic: Defense Evasion
  • Data Source: Elastic Defend
  • Data Source: Elastic Endgame
  • Data Source: Microsoft Defender for Endpoint
  • Data Source: SentinelOne
  • Data Source: Sysmon

Version: 103

Rule authors:

  • Elastic

Rule license: Elastic License v2

Rule query

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registry where host.os.type == "windows" and event.action != "deletion" and registry.value : "UserAuthentication" and
  registry.path : (
    "HKLM\\SYSTEM\\ControlSet*\\Control\\Terminal Server\\WinStations\\RDP-Tcp\\UserAuthentication",
    "\\REGISTRY\\MACHINE\\SYSTEM\\*ControlSet*\\Control\\Terminal Server\\WinStations\\RDP-Tcp\\UserAuthentication",
    "MACHINE\\SYSTEM\\*ControlSet*\\Control\\Terminal Server\\WinStations\\RDP-Tcp\\UserAuthentication"
  ) and registry.data.strings :  ("0", "0x00000000")

Framework: MITRE ATT&CKTM