Issued:
2026-09-03
Updated:
2026-09-03

RHSA-2026:63013 - Important: kernel-rt security, bug fix, and enhancement update

Synopsis

Important: kernel-rt security, bug fix, and enhancement update

Type/Severity

Security Advisory: Important

Topic

An update for kernel-rt 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-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements.

Security Fix(es):

  • kernel: s390/cpum_sf: Handle CPU hotplug remove during sampling (CVE-2024-57849)

  • kernel: smc91x: fix broken irq-context in PREEMPT_RT (CVE-2025-71132)

  • kernel: bonding: alb: fix UAF in rlb_arp_recv during bond up/down (CVE-2026-45970)

  • kernel: zram: fix use-after-free in zram_bvec_write_partial() (CVE-2026-53185)

  • kernel: pNFS: Fix use-after-free in pnfs_update_layout() (CVE-2026-63800)

  • kernel: nfsd: fix posix_acl leak on SETACL decode failure (CVE-2026-53397)

  • kernel: nfsd: release layout stid on setlease failure (CVE-2026-53399)

  • kernel: NFSv4/flexfiles: reject zero filehandle version count (CVE-2026-53392)

  • kernel: NFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr (CVE-2026-53391)

  • kernel: net: mana: validate rx_req_idx to prevent out-of-bounds array access (CVE-2026-64018)

  • kernel: Kernel: Remote out-of-bounds write in RDMA/siw (CVE-2026-64268)

  • kernel: NFSv4: include MAY_WRITE in open permission mask for O_TRUNC (CVE-2026-64298)

  • kernel: AMD-SN-7061: Safe RET Interrupt Vulnerability (CVE-2026-68480)

  • kernel: net: ipv6: use-after-free in fib6_rule_suppress due to stale res->rt6 pointer (CVE-2026-74581)

Bug Fix(es) and Enhancement(s):

  • qede: build_skb failure causes off-by-one BD ring corruption and kernel panic [rhel-8.10.z] (JIRA:RHEL-193045)

  • powerpc/pseries: lparcfg - fix kbuf[] underflow (JIRA:RHEL-240144)

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

ProductVersionArch
Red Hat Enterprise Linux for x86_64 - Extended Life Cycle8.10x86_64
Red Hat Enterprise Linux for Real Time8x86_64
Red Hat Enterprise Linux for Real Time for NFV8x86_64

Updated Packages

  • kernel-rt-debug-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-core-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-debug-modules-extra-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-kvm-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-debug-core-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-modules-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-debuginfo-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-4.18.0-553.159.1.rt7.500.el8_10.src.rpm
  • kernel-rt-modules-extra-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-debug-devel-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-debug-debuginfo-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-debuginfo-common-x86_64-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-devel-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-debug-modules-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm
  • kernel-rt-debug-kvm-4.18.0-553.159.1.rt7.500.el8_10.x86_64.rpm

Fixes

CVEs

References

Additional information