Red Hat Security Advisory: OpenShift Container Platform 4.21.25 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 4.20.30. 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/4.20/html/release_notes/ Security Fix(es): * kernel: eventpoll: fix ep_remove struct eventpoll / struct file UAF (CVE-2026-46242) * kernel: KVM: arm64: vgic-its: Drop the translation cache reference only for the erased entry (CVE-2026-46316) * kernel: KVM: x86: Fix shadow paging use-after-free due to unexpected role (CVE-2026-53359) 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 4.20 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/4.20/html-single/updating_clusters/index#updating-cluster-cli.
AI Analysis
Technical Summary
This advisory covers security fixes in Red Hat OpenShift Container Platform 4.21.25, specifically addressing three kernel vulnerabilities: CVE-2026-46242 (eventpoll: use-after-free in ep_remove involving struct eventpoll and struct file), CVE-2026-46316 (KVM arm64 vgic-its: improper translation cache reference handling), and CVE-2026-53359 (KVM x86: shadow paging use-after-free due to unexpected role). These vulnerabilities could lead to high impact on confidentiality, integrity, and availability as indicated by the CVSS vector for CVE-2026-46242. The advisory recommends upgrading to the fixed container images and packages available through the appropriate release channels.
Potential Impact
The vulnerabilities fixed in this update have a high security impact, potentially allowing local attackers with limited privileges to cause use-after-free conditions in kernel components, which can lead to system crashes or escalation of privileges affecting confidentiality, integrity, and availability. The CVSS vector for CVE-2026-46242 indicates local attack vector, low attack complexity, low privileges required, no user interaction, unchanged scope, and high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
A fix is available in Red Hat OpenShift Container Platform 4.21.25. Users should upgrade to this version using the OpenShift CLI (oc) or web console as soon as the updated packages and container images are available in their release channel. Detailed upgrade instructions are provided by Red Hat at https://docs.redhat.com/en/documentation/openshift_container_platform/4.21/html-single/updating_clusters/index#updating-cluster-cli. No additional mitigation is indicated by the vendor advisory.
Red Hat Security Advisory: OpenShift Container Platform 4.21.25 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 4.20.30. 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/4.20/html/release_notes/ Security Fix(es): * kernel: eventpoll: fix ep_remove struct eventpoll / struct file UAF (CVE-2026-46242) * kernel: KVM: arm64: vgic-its: Drop the translation cache reference only for the erased entry (CVE-2026-46316) * kernel: KVM: x86: Fix shadow paging use-after-free due to unexpected role (CVE-2026-53359) 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 4.20 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/4.20/html-single/updating_clusters/index#updating-cluster-cli.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This advisory covers security fixes in Red Hat OpenShift Container Platform 4.21.25, specifically addressing three kernel vulnerabilities: CVE-2026-46242 (eventpoll: use-after-free in ep_remove involving struct eventpoll and struct file), CVE-2026-46316 (KVM arm64 vgic-its: improper translation cache reference handling), and CVE-2026-53359 (KVM x86: shadow paging use-after-free due to unexpected role). These vulnerabilities could lead to high impact on confidentiality, integrity, and availability as indicated by the CVSS vector for CVE-2026-46242. The advisory recommends upgrading to the fixed container images and packages available through the appropriate release channels.
Potential Impact
The vulnerabilities fixed in this update have a high security impact, potentially allowing local attackers with limited privileges to cause use-after-free conditions in kernel components, which can lead to system crashes or escalation of privileges affecting confidentiality, integrity, and availability. The CVSS vector for CVE-2026-46242 indicates local attack vector, low attack complexity, low privileges required, no user interaction, unchanged scope, and high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
A fix is available in Red Hat OpenShift Container Platform 4.21.25. Users should upgrade to this version using the OpenShift CLI (oc) or web console as soon as the updated packages and container images are available in their release channel. Detailed upgrade instructions are provided by Red Hat at https://docs.redhat.com/en/documentation/openshift_container_platform/4.21/html-single/updating_clusters/index#updating-cluster-cli. No additional mitigation is indicated by the vendor advisory.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_vex
- Csaf Version
- 2.0
- Publisher
- Microsoft Security Response Center
- Advisory Id
- msrc_CVE-2026-46242
- Cve Count
- 1
- Additional Cves
- []
- Cvss Version
- 3.1
Threat ID: 6a1ca158e29bf47b505e1f5f
Added to database: 05/31/2026, 21:00:08 UTC
Last enriched: 07/30/2026, 14:47:00 UTC
Last updated: 09/04/2026, 10:52:09 UTC
Views: 215
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