RHSA-2025:23427HighCVSS 7.6

Red Hat Security Advisory: kernel security update

Published
December 17, 2025
Last Modified
July 30, 2026

🔗 CVE IDs covered (3)

CVE-2023-53401 →CVE-2025-39955 →CVE-2025-40186 →

📋 Description

CVE-2023-53401 — kernel: mm: kmem: fix a NULL pointer dereference in obj_stock_flush_required() CVE-2025-39955 — kernel: tcp: Clear tcp_sk(sk)->fastopen_rsk in tcp_disconnect() CVE-2025-40186 — kernel: Linux kernel: Privilege escalation or Denial of Service via TCP Fast Open vulnerability

🎯 Affected products74

  • Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • bpftool-0:4.18.0-477.123.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • bpftool-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • bpftool-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • bpftool-debuginfo-0:4.18.0-477.123.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • bpftool-debuginfo-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • bpftool-debuginfo-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • kernel-0:4.18.0-477.123.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-0:4.18.0-477.123.1.el8_8.src as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-0:4.18.0-477.123.1.el8_8.src as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • kernel-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • kernel-abi-stablelists-0:4.18.0-477.123.1.el8_8.noarch as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-abi-stablelists-0:4.18.0-477.123.1.el8_8.noarch as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • kernel-core-0:4.18.0-477.123.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-core-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-core-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • kernel-debug-0:4.18.0-477.123.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-debug-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-debug-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • kernel-debug-core-0:4.18.0-477.123.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-debug-core-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-debug-core-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • kernel-debug-debuginfo-0:4.18.0-477.123.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-debug-debuginfo-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-debug-debuginfo-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • kernel-debug-devel-0:4.18.0-477.123.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-debug-devel-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • kernel-debug-devel-0:4.18.0-477.123.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • +44 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. 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.

🔗 References (6)