RHSA-2026:26563 - Security Advisory

Topic

An update for kernel is now available for Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions and Red Hat Enterprise Linux 8.8 Telecommunications Update Service.

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

Security Fix(es):

• kernel: geneve: Fix use-after-free in geneve_find_dev(). (CVE-2025-21858)
• kernel: nbd: defer config unlock in nbd_genl_connect (CVE-2025-68366)
• kernel: crypto: asymmetric_keys - prevent overflow in asymmetric_key_generate_id (CVE-2025-68724)
• kernel: mlxsw: spectrum_mr: Fix use-after-free when updating multicast route stats (CVE-2025-68800)
• kernel: iommu: disable SVA when CONFIG_X86 is set (CVE-2025-71089)
• kernel: libceph: make decode_pool() more resilient against corrupted osdmaps (CVE-2025-71116)
• kernel: libceph: prevent potential out-of-bounds reads in handle_auth_done() (CVE-2026-22984)
• kernel: libceph: replace overzealous BUG_ON in osdmap_apply_incremental() (CVE-2026-22990)
• kernel: netfilter: nf_tables: release flowtable after rcu grace period on error (CVE-2026-23392)
• kernel: netfilter: ip6t_eui64: reject invalid MAC header for all packets (CVE-2026-31685)
• kernel: netfilter: ctnetlink: ensure safe access to master conntrack (CVE-2026-43116)
• kernel: wifi: brcmfmac: validate bsscfg indices in IF events (CVE-2026-43110)
• kernel: md/bitmap: fix GPF in write_page caused by resize race (CVE-2026-43163)
• kernel: netfilter: xt_tcpmss: check remaining length before reading optlen (CVE-2026-43190)
• kernel: xfs: fix freemap adjustments when adding xattrs to leaf blocks (CVE-2026-43158)
• kernel: Linux kernel: smb: client: reject userspace cifs.spnego descriptions (CVE-2026-46243)
• kernel: sctp: revalidate list cursor after sctp_sendmsg_to_asoc() in SCTP_SENDALL (CVE-2026-46227)
• kernel: wifi: mac80211: remove station if connection prep fails (CVE-2026-46125)

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 Update Support Extension 8.8 x86_64
• Red Hat Enterprise Linux Server - TUS 8.8 x86_64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 8.8 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.8 x86_64

Fixes

• BZ - 2351619 - CVE-2025-21858 kernel: geneve: Fix use-after-free in geneve_find_dev().
• BZ - 2424881 - CVE-2025-68366 kernel: nbd: defer config unlock in nbd_genl_connect
• BZ - 2424886 - CVE-2025-68724 kernel: crypto: asymmetric_keys - prevent overflow in asymmetric_key_generate_id
• BZ - 2429065 - CVE-2025-68800 kernel: mlxsw: spectrum_mr: Fix use-after-free when updating multicast route stats
• BZ - 2429104 - CVE-2025-71089 kernel: iommu: disable SVA when CONFIG_X86 is set
• BZ - 2429602 - CVE-2025-71116 kernel: libceph: make decode_pool() more resilient against corrupted osdmaps
• BZ - 2432389 - CVE-2026-22984 kernel: libceph: prevent potential out-of-bounds reads in handle_auth_done()
• BZ - 2432400 - CVE-2026-22990 kernel: libceph: replace overzealous BUG_ON in osdmap_apply_incremental()
• BZ - 2451218 - CVE-2026-23392 kernel: netfilter: nf_tables: release flowtable after rcu grace period on error
• BZ - 2461759 - CVE-2026-31685 kernel: netfilter: ip6t_eui64: reject invalid MAC header for all packets
• BZ - 2467005 - CVE-2026-43116 kernel: netfilter: ctnetlink: ensure safe access to master conntrack
• BZ - 2467014 - CVE-2026-43110 kernel: wifi: brcmfmac: validate bsscfg indices in IF events
• BZ - 2467059 - CVE-2026-43163 kernel: md/bitmap: fix GPF in write_page caused by resize race
• BZ - 2467064 - CVE-2026-43190 kernel: netfilter: xt_tcpmss: check remaining length before reading optlen
• BZ - 2467210 - CVE-2026-43158 kernel: xfs: fix freemap adjustments when adding xattrs to leaf blocks
• BZ - 2481486 - CVE-2026-46243 kernel: Linux kernel: smb: client: reject userspace cifs.spnego descriptions
• BZ - 2482564 - CVE-2026-46227 kernel: sctp: revalidate list cursor after sctp_sendmsg_to_asoc() in SCTP_SENDALL
• BZ - 2482608 - CVE-2026-46125 kernel: wifi: mac80211: remove station if connection prep fails

CVEs

• CVE-2025-21858
• CVE-2025-68366
• CVE-2025-68724
• CVE-2025-68800
• CVE-2025-71089
• CVE-2025-71116
• CVE-2026-22984
• CVE-2026-22990
• CVE-2026-23392
• CVE-2026-31685
• CVE-2026-43110
• CVE-2026-43116
• CVE-2026-43158
• CVE-2026-43163
• CVE-2026-43190
• CVE-2026-46125
• CVE-2026-46227
• CVE-2026-46243

References

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