Windows DLL Search Order Hijacking with iscsicpl
Description
The following analytic identifies a recently disclosed search ordler DLL hijack in iscsicpl.exe. The malicious DLL must be in a new path and iscsicpl.exe, upon load, will execute the payload. The analytic is restricted to Windows shells. Two proof of concepts were identified and utilized to determine the behavior. The command-line is an option to go after, but most likely identifying a child process off iscsicpl.exe will be more effective. Monitoring for suspicious DLL loads is also an option.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2022-07-29
- Author: Michael Haag, Splunk
- ID: f39ee679-3b1e-4f47-841c-5c3c580acda2
Annotations
ATT&CK
Kill Chain Phase
- Installation
- Exploitation
NIST
- DE.CM
CIS20
- CIS 10
CVE
Search
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| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.parent_process_name=iscsicpl.exe `windows_shells` by Processes.dest Processes.user Processes.parent_process_name Processes.process_name Processes.process Processes.process_id Processes.parent_process_id
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_dll_search_order_hijacking_with_iscsicpl_filter`
Macros
The SPL above uses the following Macros:
windows_dll_search_order_hijacking_with_iscsicpl_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
- Processes.dest
- Processes.user
- Processes.parent_process_name
- Processes.parent_process
- Processes.original_file_name
- Processes.process_name
- Processes.process
- Processes.process_id
- Processes.parent_process_path
- Processes.process_path
- Processes.parent_process_id
How To Implement
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
False positives may be present, filtering may be required. Remove the Windows Shells macro to determine if other utilities are using iscsicpl.exe.
Associated Analytic Story
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
64.0 | 80 | 80 | An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $user$ attempting to elevate access. |
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
- https://github.com/hackerhouse-opensource/iscsicpl_bypassUAC
- https://github.com/422926799/csplugin/tree/master/bypassUAC
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
source | version: 1