Red Hat Security Advisory: OpenShift Container Platform 4.21.18 bug fix and security update
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 4.21.18. See the following advisory for the RPM packages for this release: https://access.redhat.com/errata/RHBA-2026:21707 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/
AI Analysis
Technical Summary
This Red Hat security advisory covers the release of OpenShift Container Platform 4.21.18, which includes bug fixes and security updates for multiple vulnerabilities (CVE-2026-26996, CVE-2026-33186, CVE-2026-34986). The update addresses issues related to container images and RPM packages for the platform designed for on-premise or private cloud Kubernetes deployments. The advisory references several bug fixes and enhancements, including fixes for manual networking configuration persistence, Prometheus panics, and machine config daemon failures. The update is rated as Important by Red Hat Product Security. Users are directed to upgrade their clusters using official documentation and tools such as the OpenShift CLI (oc).
Potential Impact
The vulnerabilities addressed in this update have been rated as having an Important security impact by Red Hat, indicating a high severity level. The update mitigates multiple bugs and security issues that could affect the stability and security of OpenShift Container Platform 4.21 deployments. There are no known exploits in the wild reported at the time of this advisory. The impact is mitigated by applying the updated container images and RPM packages provided by Red Hat.
Mitigation Recommendations
Red Hat has released updated container images and RPM packages as part of OpenShift Container Platform 4.21.18 to fix the identified vulnerabilities and bugs. Users should upgrade their OpenShift clusters to this version following the official Red Hat documentation and upgrade procedures. The vendor manages remediation through these official updates. No additional mitigation actions are specified or required beyond applying the update.
Red Hat Security Advisory: OpenShift Container Platform 4.21.18 bug fix and security update
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 4.21.18. See the following advisory for the RPM packages for this release: https://access.redhat.com/errata/RHBA-2026:21707 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/
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This Red Hat security advisory covers the release of OpenShift Container Platform 4.21.18, which includes bug fixes and security updates for multiple vulnerabilities (CVE-2026-26996, CVE-2026-33186, CVE-2026-34986). The update addresses issues related to container images and RPM packages for the platform designed for on-premise or private cloud Kubernetes deployments. The advisory references several bug fixes and enhancements, including fixes for manual networking configuration persistence, Prometheus panics, and machine config daemon failures. The update is rated as Important by Red Hat Product Security. Users are directed to upgrade their clusters using official documentation and tools such as the OpenShift CLI (oc).
Potential Impact
The vulnerabilities addressed in this update have been rated as having an Important security impact by Red Hat, indicating a high severity level. The update mitigates multiple bugs and security issues that could affect the stability and security of OpenShift Container Platform 4.21 deployments. There are no known exploits in the wild reported at the time of this advisory. The impact is mitigated by applying the updated container images and RPM packages provided by Red Hat.
Mitigation Recommendations
Red Hat has released updated container images and RPM packages as part of OpenShift Container Platform 4.21.18 to fix the identified vulnerabilities and bugs. Users should upgrade their OpenShift clusters to this version following the official Red Hat documentation and upgrade procedures. The vendor manages remediation through these official updates. No additional mitigation actions are specified or required beyond applying the update.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:21709
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-33186","CVE-2026-34986"]
- Cvss Version
- null
Threat ID: 6a1f4e80e29bf47b5007c192
Added to database: 6/2/2026, 9:43:28 PM
Last enriched: 6/2/2026, 9:44:17 PM
Last updated: 6/3/2026, 5:01:04 AM
Views: 2
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