Issued at: 2026-10-27
Updated at: 2026-10-27
Advisory content derived from Red Hat RHSA-2026:89082, © Red Hat, Inc., used under CC BY 4.0, with modifications.
Synopsis
Important: kernel-rt security, bug fix, and enhancement update
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: restrict SO_ATTACH_FILTER to priv users (CVE-2026-53236)
* kernel: fuse: re-lock request before replacing page cache folio (CVE-2026-53388)
* kernel: writeback: fix race between cgroup_writeback_umount() and inode_switch_wbs() (CVE-2026-64378)
* kernel: net: gro: fix double aggregation of flush-marked skbs (CVE-2026-68136)
* kernel: net/packet: avoid fanout hook re-registration after unregister (CVE-2026-68338)
* kernel: net/iucv: fix use-after-free of a severed iucv_path (CVE-2026-68140)
* kernel: net/sched: serialize qdisc_rtab_list against concurrent get/put (CVE-2026-68138)
* kernel: ipvs: reload ip header after head reallocation (CVE-2026-68476)
* kernel: selinux: avoid sk_socket dereference in selinux_sctp_bind_connect() (CVE-2026-72242)
* kernel: mptcp: options: reset DSS fields in case of unexpected size (CVE-2026-80586)
* kernel: usb: usbfs: fix use-after-free of usb_device in usbdev_release() (CVE-2026-80824)
* kernel: smb: client: clear setuid/setgid bit on write with cifsacl/modefromsid/posix extensions (CVE-2026-89638)
* kernel: net/iucv: filter frames in afiucv_hs_rcv() by ingress device (CVE-2026-81003)
* kernel: ipv4: validate checksum_start before completing checksum (CVE-2026-99999)
Bug Fix(es) and Enhancement(s):
* Backport 6785011f8b16 ("ipv4: validate checksum_start before completing checksum") [rhel-8.10.z] (JIRA:Rocky Linux-280584)
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.