RHSA-2026:66000 - Security Advisory

Topic

An update for kernel is now available for Red Hat Enterprise Linux 8.

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

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es):

• kernel: crypto: pcrypt - Fix handling of MAY_BACKLOG requests (CVE-2026-43493)
• kernel: netfilter: conntrack: remove sprintf usage (CVE-2026-53002)
• kernel: netfilter: synproxy: refresh tcphdr after skb_ensure_writable (CVE-2026-64007)
• kernel: rhashtable: clear stale iter->p on table restart (CVE-2026-64563)
• kernel: smb: client: validate DFS referral PathConsumed (CVE-2026-68343)
• kernel: nvmet-rdma: handle inline data with a nonzero offset (CVE-2026-72129)
• kernel: net: bridge: stop fast-leave after deleting a port group (CVE-2026-74480)

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.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.

Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture.

Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available.

Affected Products

• Red Hat Enterprise Linux for x86_64 8 x86_64
• Red Hat Enterprise Linux for IBM z Systems 8 s390x
• Red Hat Enterprise Linux for Power, little endian 8 ppc64le
• Red Hat Enterprise Linux for ARM 64 8 aarch64
• Red Hat CodeReady Linux Builder for x86_64 8 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian 8 ppc64le
• Red Hat CodeReady Linux Builder for ARM 64 8 aarch64
• Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 8.10 x86_64
• Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 8.10 aarch64
• Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 8.10 ppc64le
• Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 8.10 s390x

Fixes

• BZ - 2479812 - CVE-2026-43493 kernel: crypto: pcrypt - Fix handling of MAY_BACKLOG requests
• BZ - 2492329 - CVE-2026-53002 kernel: netfilter: conntrack: remove sprintf usage
• BZ - 2502361 - CVE-2026-64007 kernel: netfilter: synproxy: refresh tcphdr after skb_ensure_writable
• BZ - 2510892 - CVE-2026-64563 kernel: rhashtable: clear stale iter->p on table restart
• BZ - 2513373 - CVE-2026-68343 kernel: smb: client: validate DFS referral PathConsumed
• BZ - 2516731 - CVE-2026-72129 kernel: nvmet-rdma: handle inline data with a nonzero offset
• BZ - 2517046 - CVE-2026-74480 kernel: net: bridge: stop fast-leave after deleting a port group

CVEs

• CVE-2026-43493
• CVE-2026-53002
• CVE-2026-64007
• CVE-2026-64563
• CVE-2026-68343
• CVE-2026-72129
• CVE-2026-74480

References

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