RHSA-2026:29833: Important: OpenShift Container Platform 4.21.22 bug fix and security update
Important: OpenShift Container Platform 4.21.22 bug fix and security update
Other sources
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 4.21.22. See the following advisory for the RPM packages for this release:https://access.redhat.com/errata/RHBA-2026:29832 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/openshiftcontainerplatform/4.21/html/releasenotes/ Security Fix(es): samba: Remote Code Execution in SAMR (CVE-2026-4408) kernel: net/sched: actpedit: extend the writable skb range per key (CVE-2026-46331) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.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 athttps://docs.redhat.com/en/documentation/openshiftcontainerplatform/4.21/html-single/updatingclusters/index#updating-cluster-cli.
— Red Hat
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
OpenShift Container Platform 4.21to a version that resolves this vulnerability.Fixed in 4.21.22Patch RHBA-2026:29832 - Compensating control
After upgrading to OpenShift Container Platform 4.21.22, ensure the cluster fully applies the asynchronous errata update per the upgrade instructions referenced for OCP 4.21.
Event History
Frequently Asked Questions
What is the severity of RHSA-2026:29833?
The severity of RHSA-2026:29833 is classified as high with a score of 7.
How do I fix RHSA-2026:29833?
To fix RHSA-2026:29833, you should update your OpenShift Container Platform to version 4.21.22.
What components are affected by RHSA-2026:29833?
RHSA-2026:29833 affects multiple Red Hat OpenShift Container Platform components, including those for IBM Z, LinuxONE, ARM 64, and Power.
What is the main focus of RHSA-2026:29833?
The main focus of RHSA-2026:29833 is to provide a bug fix and security update for the OpenShift Container Platform.
When was RHSA-2026:29833 published?
RHSA-2026:29833 was published on June 30, 2026.