RHSA-2026:57488: OpenShift Container Platform 4.18.54 security and extras 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 RPM packages for Red Hat OpenShift Container Platform 4.18.54. See the following advisory for the container images for this release:https://access.redhat.com/errata/RHSA-2026:57487 Security Fix(es): mime: golang: Golang MIME: Denial of Service via maliciously-crafted MIME header (CVE-2026-42504) net: golang: Go net package: Denial of Service via long CNAME response in LookupCNAME (CVE-2026-33811) crypto/x509: golang: golang crypto/x509: Denial of Service via excessive processing of DNS SAN entries (CVE-2026-27145) crypto/x509: crypto/tls: golang: Go: Denial of Service vulnerability in certificate chain building (CVE-2026-32280) crypto/tls: crypto/tls: Incorrect certificate validation during TLS session resumption (CVE-2025-68121) 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 4.18 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/openshiftcontainerplatform/4.18/html-single/updatingclusters/index#updating-cluster-cli.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
OpenShift Container Platform 4.18to a version that resolves this vulnerability.Fixed in 4.18.54Patch RHSA-2026:57487 - Upgrade
Upgrade
OpenShift Container Platform 4.18 container imagesto a version that resolves this vulnerability.Fixed in 4.18.54Patch RHSA-2026:57487
Event History
Frequently Asked Questions
Which deployments should apply this update?
All Red Hat OpenShift Container Platform 4.18 users are advised to upgrade to the updated packages in this advisory.
What types of attacks are addressed by the included fixes?
The fixes address denial-of-service issues involving malicious MIME headers, long CNAME responses, excessive DNS SAN processing, and certificate chain building. They also address incorrect certificate validation during TLS session resumption.
Does this advisory include the corresponding container images?
No. This advisory contains RPM packages for OpenShift Container Platform 4.18.54; a separate advisory, RHSA-2026:57487, covers the container images for this release.