RHSA-2026:62522HighCVSS 7.8

Red Hat Security Advisory: kernel-rt security update

Published
September 2, 2026
Last Modified
September 8, 2026

🔗 CVE IDs covered (2)

CVE-2026-64002 →CVE-2026-74480 →

📋 Description

CVE-2026-64002 — kernel: ipv4: free net->ipv4.sysctl_local_reserved_ports after unregister_net_sysctl_table() CVE-2026-74480 — kernel: net: bridge: stop fast-leave after deleting a port group

🎯 Affected products36

  • Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-0:5.14.0-284.190.1.rt14.475.el9_2.src as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-0:5.14.0-284.190.1.rt14.475.el9_2.src as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-core-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-core-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-debug-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-debug-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-debug-core-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-debug-core-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-debug-debuginfo-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-debug-debuginfo-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-debug-devel-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-debug-devel-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-debug-kvm-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-debug-modules-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-debug-modules-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-debug-modules-core-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-debug-modules-core-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-debug-modules-extra-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-debug-modules-extra-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-debuginfo-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-debuginfo-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-debuginfo-common-x86_64-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-debuginfo-common-x86_64-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-devel-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time E4S (v.9.2)
  • kernel-rt-devel-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • kernel-rt-kvm-0:5.14.0-284.190.1.rt14.475.el9_2.x86_64 as a component of Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)
  • +6 more not shown

✅ 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. 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. Workaround: If bridge multicast snooping is not required, it can be disabled to prevent the vulnerable code path from being reached: ``` echo 0 > /sys/class/net/<bridge>/bridge/multicast_snooping ``` The br_multicast_leave_group() code path is only reachable when multicast snooping is active, so disabling it eliminates exposure to this flaw. Alternatively, avoid toggling multicast_to_unicast on bridge ports after it has been enabled. If multicast snooping is required, ensure that multicast_to_unicast is either left at its default (disabled) or, once enabled on a port, is not subsequently disabled while the port has active multicast group memberships.

🔗 References (5)