RHSA-2026:76738HighCVSS 8.8

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

Published
October 8, 2026
Last Modified
October 26, 2026

🔗 CVE IDs covered (35)

CVE-2026-53270 →CVE-2026-63829 →CVE-2026-63994 →CVE-2026-72320 →CVE-2026-90227 →CVE-2026-93288 →CVE-2026-63794 →CVE-2026-63922 →CVE-2026-63924 →CVE-2026-80921 →CVE-2026-63920 →CVE-2026-64557 →CVE-2026-74516 →CVE-2026-80792 →CVE-2026-97417 →CVE-2026-63918 →CVE-2026-74669 →CVE-2026-46275 →CVE-2026-64078 →CVE-2026-68476 →CVE-2026-72255 →CVE-2026-74582 →CVE-2026-80775 →CVE-2026-89972 →CVE-2026-53357 →CVE-2026-64024 →CVE-2026-64132 →CVE-2026-68432 →CVE-2026-74746 →CVE-2026-45856 →CVE-2026-45860 →CVE-2026-52972 →CVE-2026-63984 →CVE-2026-63992 →CVE-2026-72052 →

📋 Description

CVE-2026-45856 — kernel: RDMA/uverbs: Validate wqe_size before using it in ib_uverbs_post_send CVE-2026-45860 — kernel: netfilter: nf_conncount: increase the connection clean up limit to 64 CVE-2026-46275 — kernel: Bluetooth: hci_uart: fix UAFs and race conditions in close and init paths CVE-2026-52972 — kernel: crypto: af_alg - Cap AEAD AD length to 0x80000000 CVE-2026-53270 — kernel: ipvs: clear the svc scheduler ptr early on edit CVE-2026-53357 — kernel: Bluetooth: fix UAF in l2cap_sock_cleanup_listen() vs l2cap_conn_del() CVE-2026-63794 — kernel: KVM: SVM: Fix page overflow in sev_dbg_crypt() for ENCRYPT path CVE-2026-63829 — kernel: net: ip_gre: require CAP_NET_ADMIN in the device netns for changelink CVE-2026-63918 — kernel: l2tp: use refcount_inc_not_zero in l2tp_session_get_by_ifname CVE-2026-63920 — kernel: ipv6: validate extension header length before copying to cmsg CVE-2026-63922 — kernel: ipv6: exthdrs: refresh nh after handling HAO option CVE-2026-63924 — kernel: ipv6: exthdrs: refresh nh pointer after ipv6_hop_jumbo() CVE-2026-63984 — kernel: ipv6: rpl: fix hdrlen overflow in ipv6_rpl_srh_decompress() CVE-2026-63992 — kernel: tunnels: do not assume transport header in iptunnel_pmtud_check_icmp() CVE-2026-63994 — kernel: tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmpv6 CVE-2026-64024 — kernel: tcp: fix stale per-CPU tcp_tw_isn leak enabling ISN prediction CVE-2026-64078 — kernel: netfilter: x_tables: add and use xtables_unregister_table_exit CVE-2026-64132 — kernel: ipv6: ioam: refresh hdr pointer before ioam6_event() CVE-2026-64557 — kernel: Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_new_connection_cb() CVE-2026-68432 — kernel: vxlan: require CAP_NET_ADMIN in the device netns for changelink CVE-2026-68476 — kernel: ipvs: reload ip header after head reallocation CVE-2026-72052 — kernel: net: ip6_gre: require CAP_NET_ADMIN in the device netns for changelink CVE-2026-72255 — kernel: netfilter: nf_queue: pin bridge device while NFQUEUE holds fake dst CVE-2026-72320 — kernel: netfilter: nft_lookup: fix catchall element handling with inverted lookups CVE-2026-74516 — kernel: KVM: SVM: Update x2APIC MSR intercepts if AVIC is inhibited while L2 is active CVE-2026-74582 — kernel: packet: use consistent hard_header_len in non-ring send paths CVE-2026-74669 — kernel: ipvs: clear IPv4 options after rebasing tunnel ICMP errors CVE-2026-74746 — kernel: netfilter: flowtable: publish GC-visible tuple last CVE-2026-80775 — kernel: futex: Fix race on the initial mm->futex.phash.ref allocation CVE-2026-80792 — kernel: ipv6: fix use-after-free in ip6_finish_output2() CVE-2026-80921 — kernel: KVM: s390: vsie: zero stale crypto bits CVE-2026-89972 — kernel: nvme: add missing SRCU grace period in error path CVE-2026-90227 — kernel: nvme/ioctl: check SUBMIT_IO with nvme_cmd_allowed() CVE-2026-93288 — kernel: netfilter: nfnetlink_log: wait for rcu grace period before freeing pernet state CVE-2026-97417 — kernel: netfilter: nf_conntrack: use get_unaligned_be32() in tcp_sack()

🎯 Affected products200

  • 10Base-SMTV
  • Red Hat Enterprise Linux AppStream (v. 10)
  • Red Hat Enterprise Linux BaseOS (v. 10)
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)
  • Red Hat Enterprise Linux Hidden (v. 10)
  • Red Hat Enterprise Linux Real Time (v. 10)
  • Red Hat Enterprise Linux Real Time for NFV (v. 10)
  • kernel-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-0:6.12.0-211.63.1.el10_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-0:6.12.0-211.63.1.el10_2.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-0:6.12.0-211.63.1.el10_2.src as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-0:6.12.0-211.63.1.el10_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-64k-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-64k-core-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-64k-debug-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-64k-debug-core-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-64k-debug-debuginfo-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • kernel-64k-debug-debuginfo-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-64k-debug-debuginfo-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)
  • kernel-64k-debug-debuginfo-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux Real Time (v. 10)
  • kernel-64k-debug-devel-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • kernel-64k-debug-devel-matched-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • kernel-64k-debug-modules-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-64k-debug-modules-core-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-64k-debug-modules-extra-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-64k-debuginfo-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • kernel-64k-debuginfo-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)
  • kernel-64k-debuginfo-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)
  • kernel-64k-debuginfo-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux Real Time (v. 10)
  • kernel-64k-devel-0:6.12.0-211.63.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • +170 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: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. Workaround: Ensure IPv6 In-situ Operations, Administration, and Maintenance (IOAM) processing is disabled across all network interfaces. By default, IOAM processing is disabled (value set to 0). If it has been enabled, disable it dynamically using sysctl: # sysctl -w net.ipv6.conf.all.ioam6_enabled=0 # sysctl -w net.ipv6.conf.default.ioam6_enabled=0 To persist these settings across system reboots, create a file in /etc/sysctl.d/: # cat << 'EOF' > /etc/sysctl.d/99-disable-ioam.conf net.ipv6.conf.all.ioam6_enabled = 0 net.ipv6.conf.default.ioam6_enabled = 0 EOF # sysctl --system Caveats: Disabling IOAM prevents the kernel from processing IPv6 IOAM trace options, which will impact network telemetry or diagnostic utilities relying on in-situ telemetry data. Warning: Runtime sysctl modifications take effect immediately without requiring a system restart; however, verify that interface-specific sysctl entries (net.ipv6.conf.<interface>.ioam6_enabled) are also set to 0 if previously configured. Workaround: If IPv6 GRE or IP-ERSpan tunnels are not in use, their respective kernel modules (`ip6_gre` and `ip6erspan`) can be blacklisted to prevent exploitation. Create a file such as `/etc/modprobe.d/disable-ip6gre.conf` with the following content: ``` install ip6_gre /bin/true install ip6erspan /bin/true ``` After creating the file, regenerate the initramfs and reboot the system for the changes to take effect. This mitigation may impact network functionality if these tunnel types are actively used. Workaround: To mitigate this issue, prevent the `ip_vs` kernel module from loading. This can be achieved by creating a blacklist rule. 1. Unload the module if currently loaded: `sudo modprobe -r ip_vs` 2. Create a blacklist configuration file: `echo "blacklist ip_vs" | sudo tee /etc/modprobe.d/disable-ip_vs.conf` 3. Rebuild the initial RAM disk to ensure the module is not loaded at boot: `sudo dracut -f` A system reboot is required for the changes to take full effect. Disabling this module will prevent the use of IP Virtual Server (IPVS) functionality. Workaround: Prevent the nfnetlink_log kernel module from being loaded by creating a configuration file: # echo "install nfnetlink_log /bin/true" > /etc/modprobe.d/disable-nfnetlink_log.conf If the module is currently loaded, attempt to unload it: # modprobe -r nfnetlink_log Caveats: If the module is in use, unloading it dynamically will fail, and a system reboot will be required for the configuration to take effect. Disabling nfnetlink_log prevents netfilter from logging packets via this netlink interface. Workaround: Systems that do not require stateful firewall, NAT, or connection tracking can eliminate exposure by unloading the nf_conntrack kernel module. On systems where conntrack is required, exposure can be reduced by applying NOTRACK rules in the raw table to bypass connection tracking on untrusted or internet-facing interfaces, ensuring the vulnerable TCP SACK parsing code path in tcp_sack() is not reached for attacker-controlled traffic.

🔗 References (39)