RHSA-2026:20087HighCVSS 8.2

Red Hat Security Advisory: OpenShift Container Platform 4.16.63 bug fix and security update

Published
May 29, 2026
Last Modified
October 30, 2026

🔗 CVE IDs covered (5)

CVE-2026-3497 →CVE-2026-27135 →CVE-2026-35535 →CVE-2026-43503 →CVE-2026-46300 →

📋 Description

CVE-2026-3497 — openssh: OpenSSH GSSAPI: Information disclosure or denial of service due to uninitialized variables CVE-2026-27135 — nghttp2: nghttp2: Denial of Service via malformed HTTP/2 frames after session termination CVE-2026-35535 — sudo: Sudo: Privilege escalation due to failure in privilege drop calls CVE-2026-43503 — kernel: net: skbuff: propagate shared-frag marker through frag-transfer helpers CVE-2026-46300 — kernel: "Fragnesia" is a variant of Dirty Frag vulnerability in the ESP/XFRM leading to Local Privilege Escalation (LPE) vulnerability in the Linux kernel

🎯 Affected products5

  • Red Hat OpenShift Container Platform 4.16
  • rhcos-aarch64-416.94.202605200242-0 as a component of Red Hat OpenShift Container Platform 4.16
  • rhcos-ppc64le-416.94.202605200242-0 as a component of Red Hat OpenShift Container Platform 4.16
  • rhcos-s390x-416.94.202605200242-0 as a component of Red Hat OpenShift Container Platform 4.16
  • rhcos-x86_64-416.94.202605200242-0 as a component of Red Hat OpenShift Container Platform 4.16

✅ Remediation

For OpenShift Container Platform 4.16 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/4.16/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 sha256:0a3e0b4e23d509a31b7a58162a4336d24c9b899a6de9aac2f930f6b558f9e4d7 (For s390x architecture) The image digest is sha256:818c1d9fb15d05bb7d6104e8aa7fca18bb46666d4eb53951680ef445d752f0ac (For ppc64le architecture) The image digest is sha256:6f2c9e2402f4a8b128c0239e3aee44a4b4735a9d558d18f06fe4e3d4f5bc5c98 (For aarch64 architecture) The image digest is sha256:746dd9a75ac3c9ed743d63b32c12de3484f74addadb1b5a00dbb004918406ba3 All OpenShift Container Platform 4.16 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/4.16/html-single/updating_clusters/index#updating-cluster-cli. Workaround: To mitigate this issue, disable GSSAPI key exchange in the OpenSSH server configuration. This prevents the server from processing GSSAPI messages, eliminating the vulnerability's attack surface. Edit `/etc/ssh/sshd_config` and add or modify the line: ``` GSSAPIKeyExchange no ``` After saving the changes, restart the `sshd` service for the mitigation to take effect. This action will prevent users from authenticating via GSSAPI. ``` # systemctl restart sshd ``` 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. Users of affected Red Hat products should install the updated sudo packages available through their product's standard update channels. Workaround: See the security bulletin for a detailed mitigation procedure.

🔗 References (6)