In Splunk Connect for Kafka versions below 2.2.7, an unauthenticated user who can reach the Kafka Connect Representational State Transfer (REST) API could configure timestamp extraction with a crafted regular expression and matching event data to block a Kafka Connect worker thread, stopping event delivery for the affected connector. The vulnerability is possible because timestamp extraction evaluates customer-supplied regular expressions without a time limit. For more information see Install Splunk Connect for Kafka (https://help.splunk.com/en/data-management/integrate-data-with-add-ons/splunk-connect-for-kafka/2.2/install/install-splunk-connect-for-kafka) and Data ingestion parameters for Splunk Connect for Kafka (https://help.splunk.com/en/data-management/integrate-data-with-add-ons/splunk-connect-for-kafka/2.2/overview/data-ingestion-parameters-for-splunk-connect-for-kafka) in the Splunk documentation.
Restrict access to the Kafka Connect Representational State Transfer (REST) API to trusted administrative hosts and networks. Turn off timestamp extraction by setting enable.timestamp.extraction to false in the connector configuration if you do not use timestamp extraction functionality. For more information see Data ingestion parameters for Splunk Connect for Kafka in the Splunk documentation.
Upgrade each affected Splunk app or add-on to the applicable fixed version listed in Product Status.