RHSA-2026:41236CriticalCVSS 8.8

Red Hat Security Advisory: kernel-rt security, bug fix, and enhancement update

Published
July 17, 2026
Last Modified
August 21, 2026

🔗 CVE IDs covered (16)

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

📋 Description

CVE-2026-23243 — kernel: Linux kernel: Denial of service and memory corruption in RDMA umad CVE-2026-23455 — kernel: netfilter: nf_conntrack_h323: check for zero length in DecodeQ931() CVE-2026-31532 — kernel: can: raw: fix ro->uniq use-after-free in raw_rcv() CVE-2026-31607 — kernel: usbip: validate number_of_packets in usbip_pack_ret_submit() CVE-2026-31685 — kernel: netfilter: ip6t_eui64: reject invalid MAC header for all packets CVE-2026-43037 — kernel: ip6_tunnel: clear skb2->cb[] in ip4ip6_err() CVE-2026-43110 — kernel: wifi: brcmfmac: validate bsscfg indices in IF events CVE-2026-43125 — kernel: dlm: validate length in dlm_search_rsb_tree CVE-2026-43158 — kernel: xfs: fix freemap adjustments when adding xattrs to leaf blocks CVE-2026-43163 — kernel: md/bitmap: fix GPF in write_page caused by resize race CVE-2026-43190 — kernel: netfilter: xt_tcpmss: check remaining length before reading optlen CVE-2026-43198 — kernel: tcp: fix potential race in tcp_v6_syn_recv_sock() CVE-2026-45852 — kernel: RDMA/rxe: Fix double free in rxe_srq_from_init CVE-2026-46090 — kernel: ALSA: aloop: Fix peer runtime UAF during format-change stop CVE-2026-46181 — kernel: RDMA/mlx4: Fix mis-use of RCU in mlx4_srq_event() CVE-2026-46243 — kernel: Linux kernel: smb: client: reject userspace cifs.spnego descriptions

🎯 Affected products13

  • Red Hat Enterprise Linux for Real Time (v. 7 ELS)
  • kernel-rt-0:3.10.0-1160.155.1.rt56.1307.el7.src as a component of Red Hat Enterprise Linux for Real Time (v. 7 ELS)
  • kernel-rt-0:3.10.0-1160.155.1.rt56.1307.el7.x86_64 as a component of Red Hat Enterprise Linux for Real Time (v. 7 ELS)
  • kernel-rt-debug-0:3.10.0-1160.155.1.rt56.1307.el7.x86_64 as a component of Red Hat Enterprise Linux for Real Time (v. 7 ELS)
  • kernel-rt-debug-debuginfo-0:3.10.0-1160.155.1.rt56.1307.el7.x86_64 as a component of Red Hat Enterprise Linux for Real Time (v. 7 ELS)
  • kernel-rt-debug-devel-0:3.10.0-1160.155.1.rt56.1307.el7.x86_64 as a component of Red Hat Enterprise Linux for Real Time (v. 7 ELS)
  • kernel-rt-debuginfo-0:3.10.0-1160.155.1.rt56.1307.el7.x86_64 as a component of Red Hat Enterprise Linux for Real Time (v. 7 ELS)
  • kernel-rt-debuginfo-common-x86_64-0:3.10.0-1160.155.1.rt56.1307.el7.x86_64 as a component of Red Hat Enterprise Linux for Real Time (v. 7 ELS)
  • kernel-rt-devel-0:3.10.0-1160.155.1.rt56.1307.el7.x86_64 as a component of Red Hat Enterprise Linux for Real Time (v. 7 ELS)
  • kernel-rt-doc-0:3.10.0-1160.155.1.rt56.1307.el7.noarch as a component of Red Hat Enterprise Linux for Real Time (v. 7 ELS)
  • kernel-rt-trace-0:3.10.0-1160.155.1.rt56.1307.el7.x86_64 as a component of Red Hat Enterprise Linux for Real Time (v. 7 ELS)
  • kernel-rt-trace-debuginfo-0:3.10.0-1160.155.1.rt56.1307.el7.x86_64 as a component of Red Hat Enterprise Linux for Real Time (v. 7 ELS)
  • kernel-rt-trace-devel-0:3.10.0-1160.155.1.rt56.1307.el7.x86_64 as a component of Red Hat Enterprise Linux for Real Time (v. 7 ELS)

✅ Remediation

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. Workaround: To mitigate this issue, prevent module ib_umad from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically. Workaround: To mitigate this issue, prevent the `can` kernel module from loading if CAN functionality is not required. This can be achieved by blacklisting the module. Create a file named `/etc/modprobe.d/blacklist-can.conf` with the following content: ``` blacklist can install can /bin/true ``` After creating the file, regenerate the initramfs and reboot the system for the changes to take effect. ```bash dracut -f -v reboot ``` This mitigation may impact systems that rely on CAN interfaces for their operation. Workaround: To mitigate this vulnerability, prevent the `usbip` kernel module from loading by blacklisting it. Create a file named `/etc/modprobe.d/blacklist-usbip.conf` with the following content: ``` blacklist usbip ``` After creating the file, regenerate the initramfs and reboot the system for the changes to take effect. This may impact functionality that relies on USB/IP. Workaround: Mitigation for this issue is to skip loading the affected module `ip6_tunnel` onto the system till we have a fix available, this can be done by a blacklist mechanism, this will ensure the driver is not loaded at the boot time. ~~~ How do I blacklist a kernel module to prevent it from loading automatically? https://access.redhat.com/solutions/41278 ~~~ We may also want to detection and monitoring an affected system as below: ~~~ Monitor for exploitation attempts: # Enable kernel audit for IPv6 tunnel operations auditctl -a always,exit -F arch=b64 -S socket -F a0=10 -F a1=3 -k ipv6_tunnel # Monitor system logs for kernel panics/crashes journalctl -k -p err -f | grep -i "ip6_tunnel\|icmp\|stack" ~~~ Workaround: To mitigate this issue, prevent module brcmfmac from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically. Workaround: Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. Workaround: To mitigate this vulnerability, prevent the `rdma_rxe` kernel module from loading. Create a file `/etc/modprobe.d/blacklist-rdma_rxe.conf` with `blacklist rdma_rxe`. Regenerate the initramfs using `sudo dracut -f -v` (or `sudo mkinitrd -f -v /boot/initramfs-$(uname -r).img $(uname -r)` for older systems) and reboot. This action may impact functionality dependent on the RDMA/rxe driver. Workaround: See the security bulletin for a detailed mitigation procedure.

🔗 References (19)