Denial of Service (DoS) through the REST API in Splunk Enterprise

Overview

In Splunk Enterprise versions below 10.4.4, 10.2.8, 10.0.11, and 9.4.16, a user who does not hold the "admin" or "power" Splunk roles could make the Splunk Enterprise instance unavailable to other users by sending a request to the Representational State Transfer (REST) API endpoint for lookup table files. The affected instance requires a restart to restore service. The vulnerability is possible because the endpoint does not limit resource use when it processes response field selections. For more information see Endpoints reference list (https://help.splunk.com/en/splunk-enterprise/rest-api-reference/10.4/introduction/endpoints-reference-list) and About configuring role-based user access (https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.4/manage-splunk-platform-users-and-roles/about-configuring-role-based-user-access) in the Splunk documentation.

Affected

• enterprise >= 10.4 < 10.4.4
• enterprise >= 10.2 < 10.2.8
• enterprise >= 10.0 < 10.0.11
• enterprise >= 9.4 < 9.4.16

Remediation

Upgrade Splunk Enterprise to versions 10.4.4, 10.2.8, 10.0.11, and 9.4.16 or higher.