Windows DLL Side-Loading Indicators for Wazuh Platform Libraries via ImageLoad Events

Alerts on suspicious loading of Wazuh platform DLLs in Windows image load telemetry, excluding common Program Files and Mingw64 patterns.

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windows-dll-side-loading-indicators-for-wazuh-platform-libraries-via-imageload-e-db77ce78

title: Windows DLL Side-Loading Indicators for Wazuh Platform Libraries via ImageLoad Events
id: 43658cae-0dce-4370-b6eb-8202bc1a1139
status: test
description: This rule flags Windows image load events where specific Wazuh-related DLLs (libwazuhshared.dll and/or libwinpthread-1.dll) are loaded from unexpected locations under Program Files or common application data paths. DLL side-loading is a common persistence and execution technique because attackers can cause a process to load attacker-controlled or out-of-place libraries. The detection relies on telemetry from image load events and applies exclusions to reduce matches from typical installation paths and known Mingw64-based library locations.
references:
  - https://www.trendmicro.com/en_us/research/23/c/iron-tiger-sysupdate-adds-linux-targeting.html
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/image_load/image_load_side_load_wazuh.yml
author: X__Junior (Nextron Systems), Huntrule Team
date: 2023-03-13
modified: 2023-05-12
tags:
  - attack.persistence
  - attack.privilege-escalation
  - attack.execution
  - attack.stealth
  - attack.t1574.001
logsource:
  category: image_load
  product: windows
detection:
  selection:
    ImageLoaded|endswith:
      - \libwazuhshared.dll
      - \libwinpthread-1.dll
  filter_main_generic:
    ImageLoaded|startswith:
      - C:\Program Files\
      - C:\Program Files (x86)\
  filter_optional_mingw64:
    ImageLoaded|contains:
      - \AppData\Local\
      - \ProgramData\
    ImageLoaded|endswith: \mingw64\bin\libwinpthread-1.dll
  condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
  - Many legitimate applications leverage this DLL. (Visual Studio, JetBrains, Ruby, Anaconda, GithubDesktop, etc.)
level: medium
license: DRL-1.1
related:
  - id: db77ce78-7e28-4188-9337-cf30e2b3ba9f
    type: derived

What it detects

This rule flags Windows image load events where specific Wazuh-related DLLs (libwazuhshared.dll and/or libwinpthread-1.dll) are loaded from unexpected locations under Program Files or common application data paths. DLL side-loading is a common persistence and execution technique because attackers can cause a process to load attacker-controlled or out-of-place libraries. The detection relies on telemetry from image load events and applies exclusions to reduce matches from typical installation paths and known Mingw64-based library locations.

Known false positives

Many legitimate applications leverage this DLL. (Visual Studio, JetBrains, Ruby, Anaconda, GithubDesktop, etc.)

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.