Splunk Enterprise lacked TLS host name certificate validation

Description

Communications between Splunk nodes and trusted hosts lacked TLS certificate host name validation in Splunk Enterprise versions before 9.0 and Splunk Cloud Platform versions before 8.2.2203.

The vulnerability requires compromising a valid certificate within the certificate authority (CA) chain for the specific customer environment or a trusted machine’s chain prior to performing a machine-in-the-middle attack. 

For Splunk Enterprise, update to Splunk Enterprise version 9.0 or higher and Configure TLS host name validation to enable the remediation. 

At the time of publishing, we have no evidence of exploitation of this vulnerability by external parties.

Solution

For Splunk Enterprise, upgrade to version 9.0 or higher and Configure TLS host name validation.

For Splunk Cloud Platform customers, Splunk is actively patching and monitoring Splunk Cloud instances.

Product Status

Severity Considerations

Splunk strongly recommends securing your Splunk environment with hardened TLS configurations. See Securing the Splunk platform with TLS for more information. However, the vulnerability assumes that you have configured your Splunk platform instances to use transport layer security (TLS) certificates for secure network connections. If you have not and are using the default certificates, the vulnerability is not applicable and is informational.

Acknowledgments

Chris Green at Splunk

Changelog

2022-07-18: Added Severity Considerations