The following analytic identifies the abuse of Syncappvpublishingserver.vbs, which is a native script on Windows that may be utilized to download remote files or perform privilege escalation.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2022-09-26
- Author: Michael Haag, Splunk
- ID: 8dd73f89-682d-444c-8b41-8e679966ad3c
Kill Chain Phase
- CIS 10
1 2 3 4 5 6 | tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_name IN ("wscript.exe","cscript.exe") Processes.process="*syncappvpublishingserver.vbs*" 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_system_script_proxy_execution_syncappvpublishingserver_filter`
The SPL above uses the following Macros:
windows_system_script_proxy_execution_syncappvpublishingserver_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
List of fields required to use this analytic.
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 if the vbscript syncappvpublishingserver is used for legitimate purposes. Filter as needed. Adding a n; to the command-line arguments may help reduce any noise.
Associated Analytic Story
|30.0||60||50||An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $user$ attempting to download files or evade critical controls.|
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
source | version: 1