Windows DLL Search Order Hijacking Hunt
Description
The following hunting analytic is an experimental query built against a accidental feature using the latest Sysmon TA 3.0 (https://splunkbase.splunk.com/app/5709/) which maps the module load (ImageLoaded) to process_name. This analytic will deprecate once this is fixed. This hunting analytic identifies known libraries in Windows that may be used in a DLL search order hijack or DLL Sideloading setting. This may require recompiling the DLL, moving the DLL or moving the vulnerable process. The query looks for any running out of system32 or syswow64. Some libraries natively run out of other application paths and will need to be added to the exclusion as needed. The lookup is comprised of Microsoft native libraries identified within the Hijacklibs.net project.
- Type: Hunting
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2022-12-31
- Author: Michael Haag, Splunk
- ID: 79c7d0fc-60c7-41be-a616-ccda752efe89
Annotations
ATT&CK
Kill Chain Phase
- Installation
- Exploitation
NIST
- DE.AE
CIS20
- CIS 10
CVE
Search
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| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime values(Processes.process_name) as process_name from datamodel=Endpoint.Processes where Processes.dest!=unknown Processes.user!=unknown NOT (Processes.process_path IN ("*\\system32\\*", "*\\syswow64\\*","*\\winsxs\\*","*\\wbem\\*")) by Processes.dest Processes.user Processes.parent_process_name Processes.process_name Processes.process_path
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `drop_dm_object_name(Processes)`
| lookup hijacklibs library AS process_name OUTPUT islibrary
| search islibrary = True
| rename parent_process_name as "Process Name" process_name AS ImageLoaded process_path AS Module_Path
| `windows_dll_search_order_hijacking_hunt_filter`
Macros
The SPL above uses the following Macros:
windows_dll_search_order_hijacking_hunt_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Lookups
The SPL above uses the following Lookups:
- hijacklibs with data
Required fields
List of fields required to use this analytic.
- _time
- Processes.dest
- Processes.user
- Processes.parent_process_name
- Processes.process_name
- Processes.process_path
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 will be present based on paths. Filter or add other paths to the exclusion as needed.
Associated Analytic Story
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
1.0 | 10 | 10 | An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $user$ attempting to perform DLL search order hijacking. |
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
source | version: 2