Strimzi: All CAs from a custom CA chain consisting of multiple CAs are trusted for mTLS user autentication

Summary

CVE	CVE-2026-27134
State	PUBLISHED
Assigner	GitHub_M
Source Priority	CVE Program / NVD first with legacy fallback
Published	2026-02-21 00:16:15 UTC
Updated	2026-06-30 03:17:53 UTC
Description	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.

Risk And Classification

Primary CVSS: v3.1 8.1 HIGH from ADP

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

EPSS: 0.003650000 probability, percentile 0.284810000 (date 2026-07-01)

Version	Source	Type	Score	Severity	Vector
3.1	ADP	CVSS	8.1	HIGH	`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`
3.1	[email protected]	Secondary	8.1	HIGH	`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`
3.1	0b0ca135-0b70-47e7-9f44-1890c2a1c46c	Secondary	8.1	HIGH	`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`
3.1	CNA	DECLARED	8.1	HIGH	`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`

CVSS v3.1 Breakdown

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

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

NVD Known Affected Configurations (CPE 2.3)

Type	Vendor	Product	Version	Update	Edition	Language
Application	Linuxfoundation	Strimzi Kafka Operator	All	All	All	All

Vendor Declared Affected Products

Source	Vendor	Product	Version	Platforms
CNA	Strimzi	Strimzi-kafka-operator	affected >= 0.49.0, < 0.50.1	Not specified
ADP	Red Hat	Streams For Apache Kafka 2	Not specified	Not specified
ADP	Red Hat	Streams For Apache Kafka 3	Not specified	Not specified

References

Reference	Source	Link	Tags
security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27134.json	0b0ca135-0b70-47e7-9f44-1890c2a1c46c	security.access.redhat.com
github.com/strimzi/strimzi-kafka-operator/releases/tag/0.50.1	[email protected]	github.com	Product, Release Notes
access.redhat.com/security/cve/CVE-2026-27134	0b0ca135-0b70-47e7-9f44-1890c2a1c46c	access.redhat.com
github.com/strimzi/strimzi-kafka-operator/security/advisories/GHSA-2qwx-...	[email protected]	github.com	Vendor Advisory
bugzilla.redhat.com/show_bug.cgi	0b0ca135-0b70-47e7-9f44-1890c2a1c46c	bugzilla.redhat.com
CVE Program record	CVE.ORG	www.cve.org	canonical
NVD vulnerability detail	NVD	nvd.nist.gov	canonical, analysis

No vendor comments have been submitted for this CVE.

Additional Advisory Data

Source	Time	Event
ADP	2026-02-21T00:01:56.960Z	Reported to Red Hat.
ADP	2026-02-20T23:05:04.320Z	Made public.

Workarounds

ADP: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

There are currently no legacy QID mappings associated with this CVE.