Windows SQL Spawning CertUtil
THIS IS A EXPERIMENTAL DETECTION
This detection has been marked experimental by the Splunk Threat Research team. This means we have not been able to test, simulate, or build datasets for this detection. Use at your own risk. This analytic is NOT supported.
Description
The following analytic detects the use of certutil to download software, specifically when spawned by SQL-related processes. This detection leverages Endpoint Detection and Response (EDR) data, focusing on command-line executions involving certutil with parameters like urlcache and split. This activity is significant as it may indicate a compromise by threat actors, such as Flax Typhoon, who use certutil to establish persistent VPN connections. If confirmed malicious, this behavior could allow attackers to maintain access, monitor system availability, and potentially escalate to data theft or ransomware deployment.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2024-05-17
- Author: Michael Haag, Splunk
- ID: dfc18a5a-946e-44ee-a373-c0f60d06e676
Annotations
Kill Chain Phase
- Command and Control
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 IN ("sqlservr.exe", "sqlagent.exe", "sqlps.exe", "launchpad.exe", "sqldumper.exe") `process_certutil` (Processes.process=*urlcache* Processes.process=*split*) OR Processes.process=*urlcache* by Processes.dest Processes.user Processes.parent_process Processes.parent_process_name Processes.process_name Processes.process Processes.process_id Processes.original_file_name Processes.parent_process_id
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_sql_spawning_certutil_filter`
Macros
The SPL above uses the following Macros:
windows_sql_spawning_certutil_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.
- Processes.dest
- Processes.user
- Processes.parent_process
- Processes.parent_process_name
- Processes.process_name
- Processes.process
- Processes.process_id
- Processes.original_file_name
- 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
The occurrence of false positives should be minimal, given that the SQL agent does not typically download software using CertUtil.
Associated Analytic Story
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
90.0 | 90 | 100 | $process_name$ was launched on $dest$ by $user$. This behavior is uncommon with the SQL process identified. |
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