name: Loading Of Dynwrapx Module
id: eac5e8ba-4857-11ec-9371-acde48001122
version: 1
date: '2021-11-18'
author: Teoderick Contreras, Splunk
type: TTP
datamodel:
- Endpoint
description: DynamicWrapperX is an ActiveX component that can be used in a script
  to call Windows API functions, but it requires the dynwrapx.dll to be installed
  and registered. With that, registering or loading dynwrapx.dll to a host is highly
  suspicious. In most instances when it is used maliciously, the best way to triage
  is to review parallel processes and pivot on the process_guid. Review the registry
  for any suspicious modifications meant to load dynwrapx.dll. Identify any suspicious
  module loads of dynwrapx.dll. This detection will return and identify the processes
  that invoke vbs/wscript/cscript.
search: '`sysmon` EventCode=7 (ImageLoaded = "*\\dynwrapx.dll" OR OriginalFileName
  = "dynwrapx.dll" OR  Product = "DynamicWrapperX") | stats count min(_time) as firstTime
  max(_time) as lastTime by Image ImageLoaded OriginalFileName Product process_name
  Computer EventCode Signed ProcessId | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`
  | `loading_of_dynwrapx_module_filter`'
how_to_implement: To successfully implement this search you need to be ingesting information
  on processes that include the name of the process responsible for the changes from
  your endpoints into the `Endpoint` datamodel in the `Processes` and `Filesystem`
  node. In addition, confirm the latest CIM App 4.20 or higher is installed and the
  latest TA for the endpoint product.
known_false_positives: False positives should be limited, however it is possible to
  filter by Processes.process_name and specific processes (ex. wscript.exe). Filter
  as needed. This may need modification based on EDR telemetry and how it brings in
  registry data. For example, removal of (Default).
references:
- https://blog.f-secure.com/hunting-for-koadic-a-com-based-rootkit/
- https://www.script-coding.com/dynwrapx_eng.html
- https://bohops.com/2018/06/28/abusing-com-registry-structure-clsid-localserver32-inprocserver32/
- https://tria.ge/210929-ap75vsddan
- https://www.virustotal.com/gui/file/cb77b93150cb0f7fe65ce8a7e2a5781e727419451355a7736db84109fa215a89
tags:
  analytic_story:
  - Remcos
  confidence: 100
  context:
  - Source:Endpoint
  - Stage:Defense Evasion
  dataset:
  - https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/malware/remcos/remcos_dynwrapx/sysmon_dynwraper.log
  impact: 80
  kill_chain_phases:
  - Exploitation
  message: dynwrapx.dll loaded by process $process_name$ on $Computer$
  mitre_attack_id:
  - T1055
  - T1055.001
  observable:
  - name: Computer
    type: Endpoint
    role:
    - Victim
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  required_fields:
  - _time
  - Image
  - ImageLoaded
  - OriginalFileName
  - Product
  - process_name
  - Computer
  - EventCode
  - Signed
  - ProcessId
  risk_score: 80
  security_domain: endpoint
  asset_type: Endpoint