RHSA-2026:44230HighCVSS 7.8

Red Hat Security Advisory: OpenShift Container Platform 4.18.50 bug fix and security update

Published
July 29, 2026
Last Modified
August 19, 2026

🔗 CVE IDs covered (3)

CVE-2026-53359 →CVE-2026-43329 →CVE-2026-46323 →

📋 Description

CVE-2026-43329 — kernel: netfilter: flowtable: strictly check for maximum number of actions CVE-2026-46323 — kernel: Linux kernel: Use-After-Free in net/gro due to improper handling of zerocopy skbs CVE-2026-53359 — kernel: KVM: x86: Fix shadow paging use-after-free due to unexpected role

🎯 Affected products5

  • Red Hat OpenShift Container Platform 4.18
  • rhcos-aarch64-418.94.202607211754-0 as a component of Red Hat OpenShift Container Platform 4.18
  • rhcos-ppc64le-418.94.202607211754-0 as a component of Red Hat OpenShift Container Platform 4.18
  • rhcos-s390x-418.94.202607211754-0 as a component of Red Hat OpenShift Container Platform 4.18
  • rhcos-x86_64-418.94.202607211754-0 as a component of Red Hat OpenShift Container Platform 4.18

✅ Remediation

For OpenShift Container Platform 4.18 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/4.18/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 sha256:06c81645f1c2c36c637297d2b2bfc9f0441ae4b78e88e8f2e9f67879a4ceddeb (For s390x architecture) The image digest is sha256:fae2a08a585617518ca1b3a5d37eb43e1b77215390223a6658bf766472b09e29 (For ppc64le architecture) The image digest is sha256:6c3bfbee4e48e56b6f0cad979e81445af095e99ebb6da0fa7d0009be26724969 (For aarch64 architecture) The image digest is sha256:95179a9a06cd4be07272fdef8276105d5d6edaa88f5ac6c28a8674e2bd2e993e All OpenShift Container Platform 4.18 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/4.18/html-single/updating_clusters/index#updating-cluster-cli. Workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. Workaround: This vulnerability can be mitigated by disabling nested virtualization. Create a file in `/etc/modprobe.d/` with a descriptive name, such as `cve-2026-53359-mitigation.conf`. In that file, disable nested virtualization for the `kvm_intel` and `kvm_amd` kernel modules: ``` options kvm-intel nested=0 options kvm-amd nested=0 ``` Use `lsmod` to determine if either module is already loaded. If so, remove loaded modules with `modprobe -r`. To validate that nested virtualization is disabled, read the files `/sys/module/kvm_intel/parameters/nested` and `/sys/module/kvm_amd/parameters/nested`. If these modules are loaded, those files should read `N` to indicate that the feature is disabled. In OpenShift 4, a MachineConfig can be utilized to create a modprobe configuration allowing control of the module on applicable nodes. See the following article for an example. https://access.redhat.com/solutions/6979679

🔗 References (6)