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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.

  • Type: TTP

  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud

  • Last Updated: 2021-11-18
  • Author: Teoderick Contreras, Splunk
  • ID: eac5e8ba-4857-11ec-9371-acde48001122

Annotations

ATT&CK

ATT&CK

ID Technique Tactic
T1055 Process Injection Defense Evasion, Privilege Escalation
T1055.001 Dynamic-link Library Injection Defense Evasion, Privilege Escalation
Kill Chain Phase
  • Exploitation
NIST
  • DE.CM
CIS20
  • CIS 10
CVE 


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`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 dest EventCode Signed ProcessId 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `loading_of_dynwrapx_module_filter`

Macros

The SPL above uses the following Macros:

:information_source: loading_of_dynwrapx_module_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Required fields

List of fields required to use this analytic.

  • _time
  • Image
  • ImageLoaded
  • OriginalFileName
  • Product
  • process_name
  • dest
  • EventCode
  • Signed
  • ProcessId

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).

Associated Analytic Story

RBA

Risk Score Impact Confidence Message
80.0 80 100 dynwrapx.dll loaded by process $process_name$ on $dest$

:information_source: The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

Reference

Test Dataset

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

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