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 use Server-Side Request Forgery (SSRF) in report notifications to send system-authenticated requests to internal Splunk services, which could allow for changes to Search Head Cluster state and a denial of service. The vulnerability is possible because Splunk Secure Gateway does not validate report notification path values before it sends internal requests.
Upgrade Splunk Secure Gateway to versions 3.10.9, 3.9.23, and 3.8.70, or higher. If you cannot upgrade Splunk Enterprise or Splunk Secure Gateway, turn off or remove the Splunk Secure Gateway app. See Manage app and add-on objects in the Splunk documentation. Note: Splunk Mobile, Spacebridge, and Mission Control rely on functionality in the Splunk Secure Gateway app. If you do not use any of these apps, features, or functionality, as a potential mitigation, you may turn off or remove the app.
Upgrade Splunk Enterprise to versions 10.4.2, 10.2.6, 10.0.9, and 9.4.14, or higher.