Insecure Default Access Control List through the REST API in Splunk Secure Gateway

In Splunk Enterprise versions below 10.4.2, 10.2.6, 10.0.9, and 9.4.14, and Splunk Secure Gateway versions below 3.10.9, 3.9.23, and 3.8.70, a user who does not hold the "admin" or "power" Splunk roles could read Spacebridge asymmetric private keys, which are secrets that compromise affected Spacebridge private-key material stored in the app collection, through the Splunk Secure Gateway App Key Value Store Representational State Transfer (REST) API. The vulnerability is possible on instances upgraded from older Splunk Secure Gateway deployments when the private-key migration remains incomplete, leaving key material in a collection with an insecure default access control list.