RHSA-2026:41236 - Security Advisory

Topic

An update for kernel-rt is now available for Red Hat Enterprise Linux 7 Extended Lifecycle Support.

Red Hat Product Security has rated this update as having a security impact of Critical. 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 and memory corruption in RDMA umad (CVE-2026-23243)
• kernel: netfilter: nf_conntrack_h323: check for zero length in DecodeQ931() (CVE-2026-23455)
• kernel: can: raw: fix ro->uniq use-after-free in raw_rcv() (CVE-2026-31532)
• kernel: usbip: validate number_of_packets in usbip_pack_ret_submit() (CVE-2026-31607)
• kernel: netfilter: ip6t_eui64: reject invalid MAC header for all packets (CVE-2026-31685)
• kernel: ip6_tunnel: clear skb2->cb[] in ip4ip6_err() (CVE-2026-43037)
• 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: tcp: fix potential race in tcp_v6_syn_recv_sock() (CVE-2026-43198)
• kernel: dlm: validate length in dlm_search_rsb_tree (CVE-2026-43125)
• kernel: Linux kernel: smb: client: reject userspace cifs.spnego descriptions (CVE-2026-46243)
• kernel: ALSA: aloop: Fix peer runtime UAF during format-change stop (CVE-2026-46090)
• kernel: RDMA/rxe: Fix double free in rxe_srq_from_init (CVE-2026-45852)
• kernel: RDMA/mlx4: Fix mis-use of RCU in mlx4_srq_event() (CVE-2026-46181)

Bug Fix(es) and Enhancement(s):

• RHEL-124698 missed the last line of the backport (JIRA:RHEL-168608)

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 Real Time for x86_64 - Extended Life Cycle Support 7 x86_64

Fixes

• BZ - 2448594 - CVE-2026-23243 kernel: Linux kernel: Denial of service and memory corruption in RDMA umad
• BZ - 2454810 - CVE-2026-23455 kernel: netfilter: nf_conntrack_h323: check for zero length in DecodeQ931()
• BZ - 2461107 - CVE-2026-31532 kernel: can: raw: fix ro->uniq use-after-free in raw_rcv()
• BZ - 2461521 - CVE-2026-31607 kernel: usbip: validate number_of_packets in usbip_pack_ret_submit()
• BZ - 2461759 - CVE-2026-31685 kernel: netfilter: ip6t_eui64: reject invalid MAC header for all packets
• BZ - 2464351 - CVE-2026-43037 kernel: ip6_tunnel: clear skb2->cb[] in ip4ip6_err()
• 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 - 2467228 - CVE-2026-43198 kernel: tcp: fix potential race in tcp_v6_syn_recv_sock()
• BZ - 2467234 - CVE-2026-43125 kernel: dlm: validate length in dlm_search_rsb_tree
• BZ - 2481486 - CVE-2026-46243 kernel: Linux kernel: smb: client: reject userspace cifs.spnego descriptions
• BZ - 2481980 - CVE-2026-46090 kernel: ALSA: aloop: Fix peer runtime UAF during format-change stop
• BZ - 2482166 - CVE-2026-45852 kernel: RDMA/rxe: Fix double free in rxe_srq_from_init
• BZ - 2482532 - CVE-2026-46181 kernel: RDMA/mlx4: Fix mis-use of RCU in mlx4_srq_event()

CVEs

• CVE-2026-23243
• CVE-2026-23455
• CVE-2026-31532
• CVE-2026-31607
• CVE-2026-31685
• CVE-2026-43037
• CVE-2026-43110
• CVE-2026-43125
• CVE-2026-43158
• CVE-2026-43163
• CVE-2026-43190
• CVE-2026-43198
• CVE-2026-45852
• CVE-2026-46090
• CVE-2026-46181
• CVE-2026-46243

References

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