Improper Access Control in System Source Types Configuration in Splunk Enterprise

In Splunk Enterprise versions below 9.4.2, 9.3.5, 9.2.7, and 9.1.10 and Splunk Cloud Platform versions below 9.3.2411.104, 9.3.2408.113, and 9.2.2406.119, a low-privileged user that does not hold the "admin" or "power" Splunk roles could create or overwrite [system source type](https://help.splunk.com/en/splunk-enterprise/get-started/get-data-in/9.2/configure-source-types/create-source-types) configurations by sending a specially-crafted payload to the `/servicesNS/nobody/search/admin/sourcetypes/` REST endpoint on the Splunk management port.