An update for kernel is now available for Red Hat Enterprise Linux 9.

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.

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

Security Fix(es):

* kernel: cxl/port: Fix use after free of parent_port in cxl_detach_ep()
(CVE-2026-31530)

* kernel: xen: AMD Zen 2 Processors: Privilege escalation via improper CPU
cache isolation (CVE-2025-54518)

* kernel: mm/slab: do not limit zeroing to orig_size when only red zoning is
enabled (CVE-2026-64368)

* kernel: net: openvswitch: reject oversized nested action attrs
(CVE-2026-64531)

Bug Fix(es) and Enhancement(s):

* Kernel oops after increasing max number of mac addresses of a mlx5 VF
[rhel-9.8.z] (JIRA:RHEL-213036)

* RHEL9.4 - s390/pkey: Check length in pkey_pckmo handler implementation
[rhel-9.8.z] (JIRA:RHEL-215578)

* RHEL9.4 - s390/pkey: Check length in PKEY_VERIFYPROTK ioctl [rhel-9.8.z]
(JIRA:RHEL-215580)

* cifs: periodic IO errors when rename races with lease break
(JIRA:RHEL-192999)

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.

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CVE-2025-54518: Insufficient Granularity of Access Control (CWE-1220)
CVE-2026-31530: Expired Pointer Dereference (CWE-825)
CVE-2026-64368: Access of Uninitialized Pointer (CWE-824)
CVE-2026-64531: Improper Handling of Length Parameter Inconsistency (CWE-130)