This Red Hat Security Advisory addresses multiple vulnerabilities in the kernel-rt packages for RHEL 8, including a critical race condition in TCPv6 connection handling (CVE-2026-43198, CVSS 9.8), a high-severity out-of-bounds read in netfilter (CVE-2026-43450, CVSS 7.1), and a high-severity SCTP flaw (CVE-2026-46227, CVSS 7.8). The vulnerabilities affect a wide range of upstream Linux kernel versions; for example, CVE-2026-43198 affects versions from 2.6.12.1 to before 6.18.16 and from 6.19 to before 6.19.6. The update provides the patched kernel-rt packages, and a system reboot is required for the changes to take effect.
Red Hat Product Errata RHSA-2026:36348 - Security Advisory Issued: 2026-07-07 Updated: 2026-07-07 RHSA-2026:36348 - Security Advisory Overview Updated Packages Synopsis Important: kernel-rt security, bug fix, and enhancement update Type/Severity Security Advisory: Important Red Hat Lightspeed patch analysis Identify and remediate systems affected by this advisory. View affected systems Topic An update for kernel-rt is now available for Red Hat Enterprise Linux 8. 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-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements. Security Fix(es): kernel: tcp: fix potential race in tcp_v6_syn_recv_sock() (CVE-2026-43198) kernel: netfilter: nfnetlink_cthelper: fix OOB read in nfnl_cthelper_dump_table() (CVE-2026-43450) kernel: sctp: revalidate list cursor after sctp_sendmsg_to_asoc() in SCTP_SENDALL (CVE-2026-46227) kernel: drm/gem: Fix inconsistent plane dimension calculation in drm_gem_fb_init_with_funcs() (CVE-2026-46209) kernel: procfs: fix missing RCU protection when reading real_parent in do_task_stat() (CVE-2026-46259) kernel: Arm Processors: Privilege escalation or information disclosure via writes to higher exception level resources (CVE-2025-10263) Bug Fix(es) and Enhancement(s): kernel panic at trailing_symlink while the task wdavdaemon runs even after 4c4f7c19b3c7 (JIRA:RHEL-152759) 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 8 x86_64 Red Hat Enterprise Linux for Real Time for NFV 8 x86_64 Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 8.10 x86_64 Fixes BZ - 2467228 - CVE-2026-43198 kernel: tcp: fix potential race in tcp_v6_syn_recv_sock() BZ - 2468228 - CVE-2026-43450 kernel: netfilter: nfnetlink_cthelper: fix OOB read in nfnl_cthelper_dump_table() BZ - 2482564 - CVE-2026-46227 kernel: sctp: revalidate list cursor after sctp_sendmsg_to_asoc() in SCTP_SENDALL BZ - 2482636 - CVE-2026-46209 kernel: drm/gem: Fix inconsistent plane dimension calculation in drm_gem_fb_init_with_funcs() BZ - 2484477 - CVE-2026-46259 kernel: procfs: fix missing RCU protection when reading real_parent in do_task_stat() BZ - 2486958 - CVE-2025-10263 kernel: Arm Processors: Privilege escalation or information disclosure via writes to higher exception level resources CVEs CVE-2025-10263 CVE-2026-43198 CVE-2026-43450 CVE-2026-46209 CVE-2026-46227 CVE-2026-46259 References https://access.redhat.com/security/updates/classification/#important Note: More recent versions of these packages may be available. Click a package name for more details. 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