In Splunk Enterprise versions below 9.2.3 and 9.1.6 and Splunk Cloud Platform versions below 9.2.2403.108 and 9.1.2312.205, a low-privileged user that does not hold the "admin" or "power" Splunk roles could create a malicious payload through a custom configuration file that the "api.uri" parameter from the "/manager/search/apps/local" endpoint in Splunk Web calls. This could result in execution of unauthorized JavaScript code in the browser of a user.
https://research.splunk.com/application/d7b5aa71-157f-4359-9c34-e35752b1d0a2/