RHSA-2026:57254 - 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: net: ieee802154: do not leave a dangling sk pointer in ieee802154_create() (CVE-2024-56602)
• kernel: ip6_gre: Use cached t->net in ip6erspan_changelink() (CVE-2026-46120)
• kernel: sched/psi: fix race between file release and pressure write (CVE-2026-52991)
• kernel: mm/huge_memory: update file PMD counter before folio_put() (CVE-2026-53189)
• kernel: scsi: target: iscsi: Fix CRC overread and double-free in iscsit_handle_text_cmd() (CVE-2026-63888)
• kernel: scsi: target: iscsi: Bound iscsi_encode_text_output() appends to rsp_buf (CVE-2026-63887)
• kernel: net/smc: reject CHID-0 ACCEPT that matches an empty ism_dev slot (CVE-2026-64048)
• kernel: smb: client: mask server-provided mode to 07777 in modefromsid (CVE-2026-64379)
• kernel: smb/client: handle overlapping allocated ranges in fallocate (CVE-2026-68388)

Bug Fix(es) and Enhancement(s):

• sfc: TX queue stalls and NIC resets caused by GFP_ATOMIC allocation failures after RHEL 8.10 kernel update (JIRA:RHEL-219767)

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 - 2334501 - CVE-2024-56602 kernel: net: ieee802154: do not leave a dangling sk pointer in ieee802154_create()
• BZ - 2482614 - CVE-2026-46120 kernel: ip6_gre: Use cached t->net in ip6erspan_changelink()
• BZ - 2492403 - CVE-2026-52991 kernel: sched/psi: fix race between file release and pressure write
• BZ - 2492788 - CVE-2026-53189 kernel: mm/huge_memory: update file PMD counter before folio_put()
• BZ - 2502443 - CVE-2026-63888 kernel: scsi: target: iscsi: Fix CRC overread and double-free in iscsit_handle_text_cmd()
• BZ - 2502447 - CVE-2026-63887 kernel: scsi: target: iscsi: Bound iscsi_encode_text_output() appends to rsp_buf
• BZ - 2502589 - CVE-2026-64048 kernel: net/smc: reject CHID-0 ACCEPT that matches an empty ism_dev slot
• BZ - 2507135 - CVE-2026-64379 kernel: smb: client: mask server-provided mode to 07777 in modefromsid
• BZ - 2513470 - CVE-2026-68388 kernel: smb/client: handle overlapping allocated ranges in fallocate

CVEs

• CVE-2024-56602
• CVE-2026-46120
• CVE-2026-52991
• CVE-2026-53189
• CVE-2026-63887
• CVE-2026-63888
• CVE-2026-64048
• CVE-2026-64379
• CVE-2026-68388

References

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