Release notes for the Splunk Add-on for Sysmon

Version 3.1.0 of the Splunk Add-on for Sysmon was released on January 2023.

Compatibility

Version 3.1.0 of the Splunk Add-on for Sysmon is compatible with the following software, CIM versions, and platforms:

Splunk platform versions	8.1, 8.2 and later
CIM	5.0 and later
Supported OS for data collection	Platform independent
Vendor products	Microsoft Sysmon version 13.33

Splunk Add-on for Sysmon field mapping changes

See the following sections for information on the differences between versions 2.0.0 of the Splunk Add-on for Microsoft Sysmon and 3.0.0 of the Splunk Add-on for Sysmon

Source-type	EventID	Fields added	Fields removed	3.0.0 extractions	3.1.0 extractions	Comments
['xmlwineventlog']	7,8	loaded_file				A new CIM field 'loaded_file' maps the file or module loaded by the process for events 7 and 8.
['xmlwineventlog']	27, 28
		process_id
		process_path
		process_exec
		eventtype
		process
		os
		action
		tag::eventtype
		process_hash
		process_guid
		dest
		process_name
		user
		vendor_product
['xmlwineventlog']				src='-'		In 3.0.0, if src extracts to '-', then the extraction is visible. In 3.1.0, we are ignoring this extraction if src only extracts '-'.
['xmlwineventlog']	3, 24			src_host='-'		In 3.0.0, if user_host extracts to '-', then the extraction is visible. In 3.1.0, we are ignoring this extraction if user_host only extracts '-'.
['xmlwineventlog']				user = '-'		In 3.0.0, if user extracts to '-', then the extraction is visible. In 3.1.0, we are ignoring this extraction if user only extracts '-'.

The dvc field is now defined for all Sysmon events. The field value shows where an event was generated The host field is mapped at search time to show the machine that generated the event. This is consistent with the Windows TA.

New features

Version 3.1.0 of the Splunk Add-on for Sysmon contains the following new and changed features:

• Sysmon could only log system action before Sysmon version 14. Version 14 introduced the following two new events:
  • Event ID 27: FileBlockExecutable. This event is generated when Sysmon detects and blocks the creation of executable files. Define rules in the Sysmon config file so Sysmon can match blocks with the activity action. This feature can be used to block certain programs the crease malicious disk files. Test the configuration files intensively before using it in Production Systems.
  • Event ID 28: FileBlockShredding. This event is generated when Sysmon detects and blocks file shredding from tools such as SDelete. Event 28 is also a block event, so some of the rules might cause issues on their System. Testing the configuration files should be performed intensively before deploying it in Production Systems.

See the following table for CIM model mapping of the new events:

Source	EventID	CIM model
XmlWinEventLog	27	Endpoint
XmlWinEventLog	28	Endpoint

Fixed issues

Version 3.1.0 of the Splunk Add-on for Sysmon fixes the following, if any, issues.

Known issues

Version 3.1.0 of the Splunk Add-on for Sysmon has the following, if any, known issues.

Date filed	Issue number	Description
2022-11-16	ADDON-58325	Correction of CIM mapping: New Sysmon TA does not map EventCode 7 Correctly
2022-11-16	ADDON-58323	Correction of CIM mapping: New Sysmon TA does not map EventCode 8 Correctly

Third-party software attributions

Version 3.1.0 of the Splunk Add-on for Sysmon does not incorporate any third-party software or libraries.