CVE-2026-76401 PUBLISHED

Regular Expression Denial of Service (DoS) through the REST API in Splunk Connect for Kafka

Assigner: cisco
Reserved: 19.08.2026 Published: 19.08.2026 Updated: 19.08.2026

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.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 5.9

Product Status

Vendor Splunk
Product Splunk Connect for Kafka
Versions
  • affected from 2.2 to 2.2.7 (excl.)

Workarounds

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.

Solutions

Upgrade each affected Splunk app or add-on to the applicable fixed version listed in Product Status.

Credits

  • Gabriel Nitu, Splunk reporter

References

Problem Types

  • An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached. cwe