On Splunk Enterprise versions below 9.0.5, 8.2.11, and 8.1.14, and in Splunk Cloud Platform versions below 9.0.2303.100, an unauthorized user can access the {{/services/indexing/preview}} REST endpoint to overwrite search results if they know the search ID (SID) of an existing search job.
https://research.splunk.com/application/bbe26f95-1655-471d-8abd-3d32fafa86f8/