RHSA-2026:83159 - Security Advisory

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: Linux kernel: Denial of Service due to use-after-free in act_tunnel_key (CVE-2026-68377)
• kernel: ASoC: SOF: ipc3-control: Fix heap overflow in bytes_ext put/get (CVE-2026-72262)
• kernel: net/sched: cls_route: fix fastmap use-after-free on filter (CVE-2026-74583)
• kernel: ALSA: usx2y: bound the hwdep mmap fault offset (CVE-2026-74641)
• kernel: udp: fix potential use-after-free in tunnel segmentation (CVE-2026-74705)
• kernel: svcrdma: Validate Read chunk positions before reconstruction (CVE-2026-89526)
• kernel: NFSD: Prevent client use-after-free during blocked-lock reaping (CVE-2026-90036)
• kernel: svcrdma: Reject Write/Reply chunks with segcount 0 (CVE-2026-93228)
• kernel: md/raid5-ppl: fix use-after-free in ppl_do_flush() (CVE-2026-93262)

Bug Fix(es) and Enhancement(s):

• powerpc/pseries: pci - logic bug in SR-IOV enable (JIRA:RHEL-240146)

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 Real Time 8 x86_64
• Red Hat Enterprise Linux for Real Time for NFV 8 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 8.10 x86_64

Fixes

• BZ - 2513277 - CVE-2026-68377 kernel: Linux kernel: Denial of Service due to use-after-free in act_tunnel_key
• BZ - 2516575 - CVE-2026-72262 kernel: ASoC: SOF: ipc3-control: Fix heap overflow in bytes_ext put/get
• BZ - 2521054 - CVE-2026-74583 kernel: net/sched: cls_route: fix fastmap use-after-free on filter
• BZ - 2521436 - CVE-2026-74641 kernel: ALSA: usx2y: bound the hwdep mmap fault offset
• BZ - 2521498 - CVE-2026-74705 kernel: udp: fix potential use-after-free in tunnel segmentation
• BZ - 2532309 - CVE-2026-89526 kernel: svcrdma: Validate Read chunk positions before reconstruction
• BZ - 2535158 - CVE-2026-90036 kernel: NFSD: Prevent client use-after-free during blocked-lock reaping
• BZ - 2540230 - CVE-2026-93228 kernel: svcrdma: Reject Write/Reply chunks with segcount 0
• BZ - 2540323 - CVE-2026-93262 kernel: md/raid5-ppl: fix use-after-free in ppl_do_flush()

CVEs

• CVE-2026-68377
• CVE-2026-72262
• CVE-2026-74583
• CVE-2026-74641
• CVE-2026-74705
• CVE-2026-89526
• CVE-2026-90036
• CVE-2026-93228
• CVE-2026-93262

References

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