RHSA-2026:29863HighCVSS 9.0

Red Hat Security Advisory: OpenShift Container Platform 4.19.36 bug fix and security update

Published
July 2, 2026
Last Modified
September 2, 2026

🔗 CVE IDs covered (6)

CVE-2026-1933 →CVE-2026-2340 →CVE-2026-3012 →CVE-2026-4408 →CVE-2026-46331 →CVE-2026-1519 →

📋 Description

CVE-2026-1519 — bind: BIND: Denial of Service via maliciously crafted DNSSEC-validated zone CVE-2026-1933 — samba: Missing access check on reparse point operations CVE-2026-2340 — samba: vfs_worm does not block directory modification CVE-2026-3012 — samba: group policy certificate enrollment uses http:// without validation CVE-2026-4408 — samba: Remote Code Execution in SAMR CVE-2026-46331 — kernel: net/sched: act_pedit: extend the writable skb range per key

🎯 Affected products5

  • Red Hat OpenShift Container Platform 4.19
  • rhcos-aarch64-4.19.9.6.202606241344-0 as a component of Red Hat OpenShift Container Platform 4.19
  • rhcos-ppc64le-4.19.9.6.202606241344-0 as a component of Red Hat OpenShift Container Platform 4.19
  • rhcos-s390x-4.19.9.6.202606241344-0 as a component of Red Hat OpenShift Container Platform 4.19
  • rhcos-x86_64-4.19.9.6.202606241344-0 as a component of Red Hat OpenShift Container Platform 4.19

✅ Remediation

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 sha256:314fe5cf32cbc22f8e400b211d530beeb027ac3d3cd5479ef953b74cf0c4676b (For s390x architecture) The image digest is sha256:4c7df105e7806009d6860cef81b0b5be58dc023df684bc43a61ed7dba5921bb6 (For ppc64le architecture) The image digest is sha256:7f60908cbff8428a398d684ce298461a7fb865fb70f4b4211bb5a8a365400c08 (For aarch64 architecture) The image digest is sha256:c771b7b0a37477cb8e88cc7acae2f1651c2a5645b84e23e091bc02b0efcf1e97 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. Workaround: To mitigate this issue, disable DNSSEC validation on affected BIND resolvers. Alternatively, configure the BIND server as authoritative-only if recursive queries are not required. Disabling DNSSEC validation may reduce the security posture of the DNS resolver. A restart of the BIND service (`named`) is required for these changes to take effect and may temporarily interrupt DNS resolution. Workaround: Administrators can mitigate this issue by ensuring users who access a read only = yes Samba share do not have filesystem-level write permission to the exported files. A server administrator may also monitor and remove unintended "user.SmbReparse" xattr (extended attributes) and the associated FILE_ATTRIBUTE_REPARSE_POINT "user.DosAttrib" bit metadata if exploitation is suspected. Workaround: Administrators can mitigate this issue by: Setting read-only permissions on protected files at the underlying filesystem level will prevent modifications. Configuring ```worm:grace_period = 0``` (zero or less) in smb.conf will eliminate the writable grace period (will eliminate the window in which the rename can happen), understanding that this may impact workflows requiring multi-step file creation. Workaround: Systems are not affected unless Samba Group Policy processing and certificate auto-enrollment are explicitly enabled. Administrators can reduce exposure by: Avoiding unnecessary use of certificate auto-enrollment. Ensuring your "smb.conf" does not contain a line like ```apply group policies = yes```. If , group policy is not be enabled, the vulnerable code will not run. Intercepting the HTTP request requires some control over the local network or other devices to intercept or redirect traffic. Some network administrators might assess this as a low risk on their networks. 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: See the security bulletin for a detailed mitigation procedure.

🔗 References (9)