RHSA-2026:44262: Important: OpenShift Container Platform 4.21.26 bug fix and security update
Important: OpenShift Container Platform 4.21.26 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 4.21.26. See the following advisory for the RPM packages for this release:https://access.redhat.com/errata/RHBA-2026:44260 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): kernel: netfilter: flowtable: strictly check for maximum number of actions (CVE-2026-43329) kernel: Linux kernel: Use-After-Free in net/gro due to improper handling of zerocopy skbs (CVE-2026-46323) 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 at https://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 4.21.26Patch RHBA-2026:44260 - Configuration
Upgrade the OpenShift Container Platform 4.21 cluster to 4.21.26 (RHBA-2026:44260) to receive the kernel security fix 'netfilter: flowtable: strictly check for maximum number of actions (CVE-2026-43329)'.
OpenShift Container Platform 4.21 (kernel netfilter) Security fix for netfilter: flowtable maximum actions (CVE-2026-43329) = updated via RHBA-2026:44260 in OCP 4.21.26 - Configuration
Upgrade the OpenShift Container Platform 4.21 cluster to 4.21.26 (RHBA-2026:44260) to receive the kernel security fix 'Use-After-Free in net/gro due to improper handling of zerocopy skbs (CVE-2026-46323)'.
OpenShift Container Platform 4.21 (kernel net/gro) Security fix for Use-After-Free in net/gro due to improper handling of zerocopy skbs (CVE-2026-46323) = updated via RHBA-2026:44260 in OCP 4.21.26 - Operational
After upgrading to OpenShift Container Platform 4.21.26, fully apply the asynchronous errata update as described in the OpenShift documentation so the updated packages/images are in effect.
Event History
Frequently Asked Questions
What is the severity of RHSA-2026:44262?
The severity of RHSA-2026:44262 is rated high with a score of 7.
What does RHSA-2026:44262 address?
RHSA-2026:44262 addresses bug fixes and security vulnerabilities in the OpenShift Container Platform 4.21.26.
How do I fix RHSA-2026:44262?
To fix RHSA-2026:44262, update your OpenShift Container Platform to version 4.21.26 or later.
What platforms are affected by RHSA-2026:44262?
RHSA-2026:44262 affects multiple platforms including Power, IBM Z and LinuxONE, and ARM 64.
What type of vulnerability is associated with RHSA-2026:44262?
RHSA-2026:44262 is associated with a 'Use After Free' vulnerability.