RHSA-2026:40762 - Security Advisory

Topic

Red Hat OpenShift Container Platform release 4.19.39 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 container images for Red Hat OpenShift Container Platform 4.19.39. See the following advisory for the RPM packages for this release:

https://access.redhat.com/errata/RHBA-2026:40761

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/4.19/html/release_notes/

Security Fix(es):

• dnsmasq: NSEC bitmap parsing infinite loop (CVE-2026-4890)
• dnsmasq: RRSIG rdlen underflow leading to heap OOB read (CVE-2026-4891)
• dnsmasq: DHCPv6 CLID buffer overflow in helper process (CVE-2026-4892)
• gnutls: gnutls: Denial of Service via DTLS packet reordering vulnerability (CVE-2026-42009)
• gnutls: gnutls: Authentication Bypass via NUL Character in Username (CVE-2026-42010)
• dnsmasq: Broken ECS source validation bypass (CVE-2026-4893)
• gnutls: gnutls: Information disclosure via heap overread in RSA key exchange (CVE-2026-5260)
• glibc: glibc: Heap Buffer Overflow in `scanf` with `%mc` format specifier and large width (CVE-2026-5450)
• gnutls: gnutls: Security bypass due to incorrect name constraint handling (CVE-2026-42011)
• gnutls: gnutls: Certificate validation bypass due to oversized Subject Alternative Name (CVE-2026-42013)

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/

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 sha256:8367df5ccbec71bfd55d827da81c659e301e17073b8a1a47e43d3e201adb4fd1

(For s390x architecture)
The image digest is sha256:8eb5fa80e5e92443a0870c876e82b03971051c4285d9f71ef025eea098448dff

(For ppc64le architecture)
The image digest is sha256:5d7790ac52e357afe0a15363f4eefd505029cc49a3fc147787cc5b96d8bbc666

(For aarch64 architecture)
The image digest is sha256:ed4761bb6a0bb26e5250aa36776dbe48d9ccab7fb1a05a253aa6ef2d59d32fde

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.

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 - 2458516 - CVE-2026-4890 dnsmasq: NSEC bitmap parsing infinite loop
• BZ - 2458517 - CVE-2026-4891 dnsmasq: RRSIG rdlen underflow leading to heap OOB read
• BZ - 2458518 - CVE-2026-4892 dnsmasq: DHCPv6 CLID buffer overflow in helper process
• BZ - 2458519 - CVE-2026-4893 dnsmasq: Broken ECS source validation bypass
• BZ - 2459853 - CVE-2026-5450 glibc: glibc: Heap Buffer Overflow in `scanf` with `%mc` format specifier and large width
• BZ - 2467279 - CVE-2026-42009 gnutls: gnutls: Denial of Service via DTLS packet reordering vulnerability
• BZ - 2467289 - CVE-2026-42010 gnutls: gnutls: Authentication Bypass via NUL Character in Username
• BZ - 2467437 - CVE-2026-42011 gnutls: gnutls: Security bypass due to incorrect name constraint handling
• BZ - 2467448 - CVE-2026-42013 gnutls: gnutls: Certificate validation bypass due to oversized Subject Alternative Name
• BZ - 2467450 - CVE-2026-5260 gnutls: gnutls: Information disclosure via heap overread in RSA key exchange

CVEs

• CVE-2026-4890
• CVE-2026-4891
• CVE-2026-4892
• CVE-2026-4893
• CVE-2026-5260
• CVE-2026-5450
• CVE-2026-42009
• CVE-2026-42010
• CVE-2026-42011
• CVE-2026-42013

References

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