Detection: Windows IOBit Unlocker Extension DLL Registration via Regsvr32

Description

Detects the IOBit Unlocker Extension being registered. IObit Unlocker is a utility designed to resolve issues involving files or folders that cannot be deleted, moved, or renamed due to being locked by other processes or applications in Windows. It's a powerful tool that can "unlock" these files or folders, terminating any processes that are using them. This allows users to manipulate these previously inaccessible files or folders as needed.

 1
 2| tstats `security_content_summariesonly`
 3  count min(_time) as firstTime
 4        max(_time) as lastTime
 5
 6from datamodel=Endpoint.Processes where
 7
 8Processes.process="*IObitUnlockerExtension.dll*"
 9Processes.process_name="regsvr32.exe"
10
11by Processes.process Processes.vendor_product Processes.user_id Processes.process_hash
12   Processes.parent_process_name Processes.parent_process_exec Processes.action
13   Processes.dest Processes.process_current_directory Processes.process_path
14   Processes.process_integrity_level Processes.original_file_name Processes.parent_process
15   Processes.parent_process_path Processes.parent_process_guid Processes.parent_process_id
16   Processes.process_guid Processes.process_id Processes.user Processes.process_name
17
18
19| `drop_dm_object_name(Processes)`
20
21| `security_content_ctime(firstTime)`
22
23| `security_content_ctime(lastTime)`
24
25| `windows_iobit_unlocker_extension_dll_registration_via_regsvr32_filter`

Data Source

Name Platform Sourcetype Source
CrowdStrike ProcessRollup2 Other 'crowdstrike:events:sensor' 'crowdstrike'
Sysmon EventID 1 Windows icon Windows 'XmlWinEventLog' 'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'
Windows Event Log Security 4688 Windows icon Windows 'XmlWinEventLog' 'XmlWinEventLog:Security'

Macros Used

Name Value
security_content_ctime convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)
windows_iobit_unlocker_extension_dll_registration_via_regsvr32_filter search *
windows_iobit_unlocker_extension_dll_registration_via_regsvr32_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK
+ Kill Chain Phases
+ NIST
+ CIS
- Threat Actors
ID Technique Tactic
T1218.010 Regsvr32 Stealth
Exploitation
DE.CM
CIS 10

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting Value
Disabled true
Cron Schedule 0 * * * *
Earliest Time -70m@m
Latest Time -10m@m
Schedule Window auto
Creates Notable Yes
Rule Title %name%
Rule Description %description%
Notable Event Fields user, dest
Creates Risk Event True
This configuration file applies to all detections of type TTP. These detections will use Risk Based Alerting and generate Notable Events.

Implementation

The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the Processes node of the Endpoint data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.

Known False Positives

Some legitimate users may run IObit Unlocker to manage locked files for maintenance or troubleshooting. Filter detections for approved use to reduce false alerts.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message:

Potential IOBit Unlocker Extension DLL activity observed on $dest$ via $process$.

Risk Object Risk Object Type Risk Score Threat Objects
dest system 50 parent_process_name

References

Detection Testing

Test Type Status Dataset Source Sourcetype
Validation Passing N/A N/A N/A
Unit Passing Dataset XmlWinEventLog:Security XmlWinEventLog
Integration ✅ Passing Dataset XmlWinEventLog:Security XmlWinEventLog

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


Source: GitHub | Version: 1