RHSA-2026:34769 - Security Advisory

Topic

Red Hat OpenShift Container Platform release 4.21.23 is now available with updates to packages and images that fix several bugs and add enhancements.

This release includes a security update for Red Hat OpenShift Container Platform 4.21.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

Red Hat OpenShift Container Platform is Red Hat's cloud computing Kubernetes application platform solution designed for on-premise or private cloud deployments.

This advisory contains the container images for Red Hat OpenShift Container Platform 4.21.23. See the following advisory for the RPM packages for this release:

https://access.redhat.com/errata/RHBA-2026:34759

Space precludes documenting all of the container images in this advisory. See the following Release Notes documentation, which will be updated shortly for this release, for details about these changes:

https://docs.redhat.com/en/documentation/openshift_container_platform/4.21/html/release_notes/

Solution

For OpenShift Container Platform 4.21 see the following documentation, which will be updated shortly for this release, for important instructions on how to upgrade your cluster and fully apply this asynchronous errata update:

https://docs.redhat.com/en/documentation/openshift_container_platform/4.21/html/release_notes/

You may download the oc tool and use it to inspect release image metadata for x86_64, s390x, ppc64le, and aarch64 architectures. The image digests may be found at https://quay.io/repository/openshift-release-dev/ocp-release?tab=tags.

The sha values for the release are as follows:

(For x86_64 architecture)
The image digest is sha256:c58d65eeaf399b6850e5cc637a199ed44066819ccbc25877a6afd44ff861d841

(For s390x architecture)
The image digest is sha256:5c89334e4cf13c60df32762ea475b863c7eeb5bc2cc5dafbbf65fc5351f520c6

(For ppc64le architecture)
The image digest is sha256:d723c3c1ca165d75bbef247f412664c36bee48ac9ce26cbddf37553c9bb736f1

(For aarch64 architecture)
The image digest is sha256:588cfd15da44d83f3f6375545de8c3e08c4a10f02a6f591a4b5d2e8ffe427497

All OpenShift Container Platform 4.21 users are advised to upgrade to these updated packages and images when they are available in the appropriate release channel. To check for available updates, use the OpenShift CLI (oc) or web console. Instructions for upgrading a cluster are available at https://docs.redhat.com/en/documentation/openshift_container_platform/4.21/html-single/updating_clusters/index#updating-cluster-cli.

Affected Products

• Red Hat OpenShift Container Platform

Fixes

• BZ - 2449833
• BZ - 2457729
• OCPBUGS-82146 - [release-4.21] - CIO should never create a second OSSM subscription
• OCPBUGS-85550 - [release-4.21] "istiod-openshift-gateway" Controller is not started when GatewayClass is created on clusters without "Marketplace" capability
• OCPBUGS-86806 - Error in OpenShift Dashboards "many-to-many matching not allowed: matching labels must be unique on one side"
• OCPBUGS-88295 - [release-4.21] Gateway API OSSM operator fails to upgrade with OLM
• OCPBUGS-88297 - [release-4.21] CIO runs at DEBUG log level by default, causing excessive log volume with Sail Library integration
• OCPBUGS-89328 - Deleted UltraSSD_LRS Azure Disk VolumeSnapshotContent resources get hung in OpenShift if the operation fails in Azure
• OCPBUGS-90553 - Cluster Overview Error Pod Count Link Does Not Apply Filter on Pods Page
• OCPBUGS-90554 - [4.21] Parallel deployments of SNO may never be powered on by metal3
• OCPBUGS-93937 - Bootstrap MCS logging entire ignition

CVEs

• CVE-2026-33186
• CVE-2026-35469

References

• https://access.redhat.com/security/updates/classification/