RHSA-2026:68534 - Security Advisory

Topic

Red Hat OpenShift Container Platform release 4.19.48 is now available with updates to packages and images that fix several bugs and add enhancements.

This release includes a security update for Red Hat OpenShift Container Platform 4.19.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

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 RPM packages for Red Hat OpenShift Container Platform 4.19.48. See the following advisory for the container images for this release:

https://access.redhat.com/errata/RHSA-2026:68540

Security Fix(es):

• net: golang: Go net package: Denial of Service via long CNAME response in LookupCNAME (CVE-2026-33811)
• encoding/asn1: golang: Go encoding/asn1: Denial of Service via excessive recursion in Unmarshal (CVE-2026-33818)
• net/mail: golang: Go net/mail: Denial of Service via crafted email inputs (CVE-2026-39820)
• golang.org/x/net/idna: golang: net/http: golang.org/x/net/idna: Privilege escalation via incorrect Punycode label processing (CVE-2026-39821)
• net/mail: golang: net/mail: Denial of Service via pathological email address parsing (CVE-2026-42499)
• mime: golang: Golang MIME: Denial of Service via maliciously-crafted MIME header (CVE-2026-42504)
• html/template: golang: Go html/template: Cross-Site Scripting via pathological input (CVE-2026-56858)
• encoding/xml: golang: Go: Denial of Service via XML decoding recursion depth issue (CVE-2026-56859)
• net/url: golang: golang net/url: Denial of Service from quadratic complexity in path resolution (CVE-2026-56860)
• crypto/tls: golang: Golang crypto/tls: Denial of Service via indefinite KeyUpdate messages (CVE-2026-56862)

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 4.19 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/4.19/html-single/updating_clusters/index#updating-cluster-cli.

Solution

For OpenShift Container Platform 4.19 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/4.19/html/release_notes/

Affected Products

• Red Hat OpenShift Container Platform 4.19 for RHEL 9 x86_64
• Red Hat OpenShift Container Platform 4.19 for RHEL 8 x86_64
• Red Hat OpenShift Container Platform for Power 4.19 for RHEL 9 ppc64le
• Red Hat OpenShift Container Platform for Power 4.19 for RHEL 8 ppc64le
• Red Hat OpenShift Container Platform for IBM Z and LinuxONE 4.19 for RHEL 9 s390x
• Red Hat OpenShift Container Platform for IBM Z and LinuxONE 4.19 for RHEL 8 s390x
• Red Hat OpenShift Container Platform for ARM 64 4.19 for RHEL 9 aarch64
• Red Hat OpenShift Container Platform for ARM 64 4.19 for RHEL 8 aarch64

Fixes

• BZ - 2467809 - CVE-2026-42499 net/mail: golang: net/mail: Denial of Service via pathological email address parsing
• BZ - 2467820 - CVE-2026-39820 net/mail: golang: Go net/mail: Denial of Service via crafted email inputs
• BZ - 2467822 - CVE-2026-33811 net: golang: Go net package: Denial of Service via long CNAME response in LookupCNAME
• BZ - 2480756 - CVE-2026-39821 golang.org/x/net/idna: golang: net/http: golang.org/x/net/idna: Privilege escalation via incorrect Punycode label processing
• BZ - 2484204 - CVE-2026-42504 mime: golang: Golang MIME: Denial of Service via maliciously-crafted MIME header
• BZ - 2515815 - CVE-2026-33818 encoding/asn1: golang: Go encoding/asn1: Denial of Service via excessive recursion in Unmarshal
• BZ - 2515820 - CVE-2026-56860 net/url: golang: golang net/url: Denial of Service from quadratic complexity in path resolution
• BZ - 2515838 - CVE-2026-56858 html/template: golang: Go html/template: Cross-Site Scripting via pathological input
• BZ - 2515839 - CVE-2026-56862 crypto/tls: golang: Golang crypto/tls: Denial of Service via indefinite KeyUpdate messages
• BZ - 2515840 - CVE-2026-56859 encoding/xml: golang: Go: Denial of Service via XML decoding recursion depth issue

CVEs

• CVE-2026-33811
• CVE-2026-33818
• CVE-2026-39820
• CVE-2026-39821
• CVE-2026-42499
• CVE-2026-42504
• CVE-2026-56858
• CVE-2026-56859
• CVE-2026-56860
• CVE-2026-56862

References

• https://access.redhat.com/security/updates/classification/#important