RHSA-2026:2490 - Security Advisory

Topic

An update for kernel is now available for Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions, and Red Hat Enterprise Linux 8.6 Telecommunications Update Service.

Red Hat Product Security has rated this update as having a security impact of Moderate. 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: efivarfs: Fix slab-out-of-bounds in efivarfs_d_compare (CVE-2025-39817)
• kernel: net/mlx5e: Check for NOT_READY flag state after locking (CVE-2023-53581)
• kernel: Bluetooth: hci_event: call disconnect callback before deleting conn (CVE-2023-53673)
• kernel: ASoC: Intel: bytcr_rt5640: Fix invalid quirk input mapping (CVE-2025-40154)
• kernel: mptcp: fix race condition in mptcp_schedule_work() (CVE-2025-40258)
• kernel: Linux kernel Bluetooth L2CAP: Kernel crash due to use-after-free via race condition (CVE-2023-53751)
• kernel: Linux kernel: Out-of-bounds write in fbdev can lead to privilege escalation, information disclosure, or denial of service. (CVE-2025-40304)
• kernel: Linux kernel: Information disclosure and denial of service via out-of-bounds read in font glyph handling (CVE-2025-40322)
• kernel: ext4: fix use-after-free in ext4_orphan_cleanup (CVE-2022-50673)
• kernel: drm/i915: Fix NULL ptr deref by checking new_crtc_state (CVE-2023-53833)
• kernel: net: atlantic: fix fragment overflow handling in RX path (CVE-2025-68301)
• kernel: NFSv4/pNFS: Clear NFS_INO_LAYOUTCOMMIT in pnfs_mark_layout_stateid_invalid (CVE-2025-68349)
• kernel: tcp: fix a signed-integer-overflow bug in tcp_add_backlog() (CVE-2022-50865)

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.

Affected Products

• Red Hat Enterprise Linux for x86_64 - Extended Life Cycle Long Life 8.6 x86_64
• Red Hat Enterprise Linux Server - AUS 8.6 x86_64
• Red Hat Enterprise Linux Server - TUS 8.6 x86_64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.6 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.6 x86_64

Fixes

• BZ - 2395805 - CVE-2025-39817 kernel: efivarfs: Fix slab-out-of-bounds in efivarfs_d_compare
• BZ - 2401545 - CVE-2023-53581 kernel: net/mlx5e: Check for NOT_READY flag state after locking
• BZ - 2402193 - CVE-2023-53673 kernel: Bluetooth: hci_event: call disconnect callback before deleting conn
• BZ - 2414494 - CVE-2025-40154 kernel: ASoC: Intel: bytcr_rt5640: Fix invalid quirk input mapping
• BZ - 2418876 - CVE-2025-40258 kernel: mptcp: fix race condition in mptcp_schedule_work()
• BZ - 2419858 - CVE-2023-53751 kernel: Linux kernel Bluetooth L2CAP: Kernel crash due to use-after-free via race condition
• BZ - 2419870 - CVE-2025-40304 kernel: Linux kernel: Out-of-bounds write in fbdev can lead to privilege escalation, information disclosure, or denial of service.
• BZ - 2419902 - CVE-2025-40322 kernel: Linux kernel: Information disclosure and denial of service via out-of-bounds read in font glyph handling
• BZ - 2420347 - CVE-2022-50673 kernel: ext4: fix use-after-free in ext4_orphan_cleanup
• BZ - 2420366 - CVE-2023-53833 kernel: drm/i915: Fix NULL ptr deref by checking new_crtc_state
• BZ - 2422836 - CVE-2025-68301 kernel: net: atlantic: fix fragment overflow handling in RX path
• BZ - 2424880 - CVE-2025-68349 kernel: NFSv4/pNFS: Clear NFS_INO_LAYOUTCOMMIT in pnfs_mark_layout_stateid_invalid
• BZ - 2426226 - CVE-2022-50865 kernel: tcp: fix a signed-integer-overflow bug in tcp_add_backlog()

CVEs

• CVE-2022-50673
• CVE-2022-50865
• CVE-2023-53581
• CVE-2023-53673
• CVE-2023-53751
• CVE-2023-53833
• CVE-2025-39817
• CVE-2025-40154
• CVE-2025-40258
• CVE-2025-40304
• CVE-2025-40322
• CVE-2025-68301
• CVE-2025-68349

References

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