CVE-2026-27134: high-severity vulnerability in strimzi-kafka-operator
Strimzi: All CAs from a custom CA chain consisting of multiple CAs are trusted for mTLS user autentication
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.1epss 0.4%
Strimzi provides a way to run an Apache Kafka cluster on Kubernetes or OpenShift in various deployment configurations. In versions 0.49.0 through 0.50.0, when using a custom Cluster or Clients CA with a multistage CA chain consisting of multiple CAs, Strimzi incorrectly configures the trusted certificates for mTLS authentication on the internal as well as user-configured listeners. All CAs from the CA chain will be trusted. And users with certificates signed by any of the CAs in the chain will be able to authenticate. This issue affects only users using a custom Cluster or Clients CA with a multistage CA chain consisting of multiple CAs. It does not affect users using the Strimzi-managed Cluster and Clients CAs. It also does not affect users using custom Cluster or Clients CA with only a single CA (i.e., no CA chain with multiple CAs). This issue has been fixed in version 0.50.1. To workaround this issue, instead of providing the full CA chain as the custom CA, users can provide only the single CA that should be used.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
strimzi · strimzi-kafka-operatorRelated CVEs — strimzi-kafka-operator
In the same product, most dangerous first.
CVE-2026-55225HIGHStrimzi: Cross-namespace privilege escalation via `Kafka.spec.entityOperator`EPSS 0.3%CVE-2026-55226MEDIUMStrimzi: Unrestricted access to all Secrets within namespace watched by the Topic operatorEPSS 0.3%CVE-2026-27133MEDIUMStrimzi All CAs from CA chain will be trusted in Kafka Connect and Kafka MirrorMaker 2 target clustersEPSS 0.2%CVE-2025-66623HIGHStrimzi allows unrestricted access to all Secrets in the same Kubernetes namespace from Kafka Connect and MirrorMaker 2 operandsEPSS 0.2%
References
https://access.redhat.com/security/cve/CVE-2026-27134https://bugzilla.redhat.com/show_bug.cgi?id=2441564https://github.com/strimzi/strimzi-kafka-operator/releases/tag/0.50.1https://github.com/strimzi/strimzi-kafka-operator/security/advisories/GHSA-2qwx-rq6j-8r6jhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27134.json