Vulnerability in Splunk Connect For Kafka

CVE-2026-76403

In Splunk Connect for Kafka versions below 2.2.7, an unauthenticated user positioned in the network path could read or alter all relevant data sent from the connector when Kerberos authentication is used with Hypertext Transfer Protocol (HTTP) Event Collector in Splunk Enterprise. The vulnerability is possible because the Kerberos authentication path does not apply the configured certificate validation options when it builds the HTTP client. 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), Security configurations for Splunk Connect for Kafka (https://help.splunk.com/en/splunk-enterprise/get-data-in/splunk-connect-for-kafka/2.2/configure/security-configurations-for-splunk-connect-for-kafka), and Set up and use HTTP Event Collector with configuration files (https://help.splunk.com/en/splunk-enterprise/get-data-in/get-started-with-getting-data-in/9.4/get-data-with-http-event-collector/set-up-and-use-http-event-collector-with-configuration-files) in the Splunk documentation.

Vulnerability class: Improper Certificate Validation

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.002 (14.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 14.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-76403: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-76403?
CVE-2026-76403 is a high-severity vulnerability in Splunk Connect For Kafka, classified under Improper Certificate Validation. CVSS score: 7.4/10. Published 2026-08-19.
How severe is CVE-2026-76403?
High severity. CVSS v3 base score is 7.4 out of 10.