Potential WPAD Spoofing via DNS Record Creation

edit

Potential WPAD Spoofing via DNS Record Creation

edit

Identifies the creation of a DNS record that is potentially meant to enable WPAD spoofing. Attackers can disable the Global Query Block List (GQBL) and create a "wpad" record to exploit hosts running WPAD with default settings for privilege escalation and lateral movement.

Rule type: eql

Rule indices:

  • winlogbeat-*
  • logs-system.*
  • logs-windows.*

Severity: medium

Risk score: 47

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: Credential Access
  • Data Source: Active Directory
  • Use Case: Active Directory Monitoring

Version: 1

Rule authors:

  • Elastic

Rule license: Elastic License v2

Setup

edit

Setup

The Audit Directory Service Changes logging policy must be configured for (Success, Failure). Steps to implement the logging policy with Advanced Audit Configuration:

Computer Configuration >
Policies >
Windows Settings >
Security Settings >
Advanced Audit Policies Configuration >
Audit Policies >
DS Access >
Audit Directory Service Changes (Success,Failure)

The above policy does not cover the target object by default (we still need it to be configured to generate events), so we need to set up an AuditRule using https://github.com/OTRF/Set-AuditRule.

Set-AuditRule -AdObjectPath 'AD:\CN=MicrosoftDNS,DC=DomainDNSZones,DC=Domain,DC=com' -WellKnownSidType WorldSid -Rights CreateChild -InheritanceFlags Descendents -AttributeGUID e0fa1e8c-9b45-11d0-afdd-00c04fd930c9 -AuditFlags Success

Rule query

edit
any where host.os.type == "windows" and event.action == "Directory Service Changes" and
    event.code == "5137" and winlog.event_data.ObjectDN : "DC=wpad,*"

Framework: MITRE ATT&CKTM