RHSA-2026:65851HighCVSS 8.6

Red Hat Security Advisory: OpenShift Container Platform 4.18.55 bug fix and security update

Published
September 17, 2026
Last Modified
October 1, 2026

🔗 CVE IDs covered (18)

CVE-2026-11822 →CVE-2026-39821 →CVE-2026-1519 →CVE-2026-14164 →CVE-2026-43112 →CVE-2026-3012 →CVE-2026-5946 →CVE-2026-15816 →CVE-2026-16313 →CVE-2026-29111 →CVE-2026-2340 →CVE-2026-3039 →CVE-2026-10723 →CVE-2026-11824 →CVE-2026-13321 →CVE-2026-3833 →CVE-2026-6893 →CVE-2026-11331 →

📋 Description

CVE-2026-1519 — bind: BIND: Denial of Service via maliciously crafted DNSSEC-validated zone CVE-2026-2340 — samba: vfs_worm does not block directory modification CVE-2026-3012 — samba: group policy certificate enrollment uses http:// without validation CVE-2026-3039 — bind: BIND 9 server memory exhaustion during GSS-API TKEY negotiation CVE-2026-3833 — gnutls: GnuTLS: Policy bypass due to case-sensitive nameConstraints comparison CVE-2026-5946 — bind: BIND: Denial of Service via specially crafted DNS messages CVE-2026-6893 — dracut: dracut: Root code execution via DHCP options command injection CVE-2026-10723 — bind: bind9: Incorrect acceptance of NSEC3 records CVE-2026-11331 — bind9: bind: Potential wildcard CNAME RPZ policy bypass CVE-2026-11822 — sqlite: SQLite: Arbitrary code execution via crafted FTS5 full-text search data CVE-2026-11824 — sqlite: SQLite: Arbitrary code execution and crash via heap-based buffer overflow in FTS5 CVE-2026-13321 — bind: bind9: DNSSEC Validation Bypass via Out-of-Zone NSEC Next Field CVE-2026-14164 — libarchive: Double-Free Vulnerability in RAR5 Decompression Logic via dangling filtered_buf pointer in init_unpack() CVE-2026-15816 — dracut: dracut: root code execution via unescaped error message written to sourced emergency hook script in die() CVE-2026-16313 — sg3_utils: sg3_utils: arbitrary command execution via udev property injection in sg_inq --export CVE-2026-29111 — systemd: systemd: Arbitrary code execution or Denial of Service via spurious IPC API call data CVE-2026-39821 — golang.org/x/net/idna: golang: net/http: golang.org/x/net/idna: Privilege escalation via incorrect Punycode label processing CVE-2026-43112 — kernel: fs/smb/client: fix out-of-bounds read in cifs_sanitize_prepath

🎯 Affected products5

  • Red Hat OpenShift Container Platform 4.18
  • rhcos-aarch64-418.94.202609031320-0 as a component of Red Hat OpenShift Container Platform 4.18
  • rhcos-ppc64le-418.94.202609031320-0 as a component of Red Hat OpenShift Container Platform 4.18
  • rhcos-s390x-418.94.202609031320-0 as a component of Red Hat OpenShift Container Platform 4.18
  • rhcos-x86_64-418.94.202609031320-0 as a component of Red Hat OpenShift Container Platform 4.18

✅ Remediation

For OpenShift Container Platform 4.18 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/4.18/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 sha256:77724a6074081531299a1f3136ade3f5491d252a5b502a4e26e82f2c65213b95 (For s390x architecture) The image digest is sha256:be975cbbdf062e07034927f71324a11d2df4321af174e7a6f655db0051e3e749 (For ppc64le architecture) The image digest is sha256:c9a14d5097f91a7d01e068a15f6899c53359a3a3e021d96bb68f11eb3e73072c (For aarch64 architecture) The image digest is sha256:d4b9d6050c259b416b19a91f3a5b25c0dd48803c272991a723f1a32866da420a 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/openshift_container_platform/4.18/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: 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. Example: ```bash # Edit /etc/named.conf and remove or comment out lines related to tkey-gssapi-keytab or tkey-gssapi-credential. # For example, remove or comment out: # key "gssapi-key" { # algorithm GSSAPI; # secret "BASE64_ENCODED_KEY"; # }; # # Then reload the named service: systemctl reload named ``` Reloading the `named` service may cause a brief interruption in DNS resolution. 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: 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: To mitigate this issue, ensure that systems configured to obtain network settings via DHCP in the initramfs are only booted on trusted networks. This vulnerability requires an attacker to control a DHCP server on the adjacent network segment. If network configuration via DHCP is not strictly necessary during the initramfs phase, consider using static network configuration. Workaround: Disclaimer: The following mitigation notes are provided as a courtesy, pending the application of an official patch. This content was generated utilizing AI tools in conjunction with data from cmetaxonomy.org. Customers are advised to independently evaluate and test these temporary mitigations within their own infrastructure. ISC states no workarounds exist. Until patched, restrict the resolver to authorized client networks and deploy separate resolvers per trust zone. Memory hardening and auth controls don't apply — this is a DNS protocol logic error using validly-signed records. Workaround: No mitigation is currently available that meets Red Hat Product Security's standards for usability, deployment, applicability, or stability. Customers are advised to apply the appropriate security update once it becomes available. Workaround: Restrict DHCP server access on networks used for network boot (DHCP snooping, dedicated/trusted provisioning VLANs) until a fix is available. Workaround: Remove or comment out the REMOVE_CMD rule from 50-udev-default.rules to prevent command execution on device removal. Alternatively, if automatic SCSI device identification is not required, disable the udev rule that invokes sg_inq --export on device connection. Workaround: Upgrade to a fixed golang.org/x/net release that includes the idna correction, via updated golang or dependent package rebuilds. Workaround: To mitigate this issue, prevent the `cifs` kernel module from loading if CIFS client functionality is not required. This can be achieved by blacklisting the module. Create a file named `/etc/modprobe.d/blacklist-cifs.conf` with the following content: ``` blacklist cifs ``` After creating the file, regenerate the initramfs and reboot the system for the changes to take effect. ```bash dracut -f -v reboot ``` Disabling the `cifs` module will prevent the system from mounting CIFS network shares, which may impact functionality relying on this protocol.

🔗 References (23)