RHSA-2026:76739HighCVSS 8.8

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

Published
October 8, 2026
Last Modified
October 14, 2026

🔗 CVE IDs covered (38)

CVE-2025-40149 →CVE-2026-52942 →CVE-2026-72052 →CVE-2026-53049 →CVE-2026-63922 →CVE-2026-68432 →CVE-2026-72099 →CVE-2026-74569 →CVE-2026-74746 →CVE-2026-80792 →CVE-2026-45861 →CVE-2026-63829 →CVE-2026-63920 →CVE-2026-63924 →CVE-2026-72255 →CVE-2026-89480 →CVE-2026-97417 →CVE-2026-53357 →CVE-2026-93288 →CVE-2026-46076 →CVE-2026-46275 →CVE-2026-63992 →CVE-2026-64557 →CVE-2026-23442 →CVE-2026-46317 →CVE-2026-63994 →CVE-2026-43332 →CVE-2026-63993 →CVE-2026-64385 →CVE-2026-72289 →CVE-2026-74669 →CVE-2026-80921 →CVE-2026-89481 →CVE-2026-52986 →CVE-2026-63984 →CVE-2026-74516 →CVE-2026-89972 →CVE-2026-90227 →

📋 Description

CVE-2025-40149 — kernel: tls: Use __sk_dst_get() and dst_dev_rcu() in get_netdev_for_sock() CVE-2026-23442 — kernel: ipv6: add NULL checks for idev in SRv6 paths CVE-2026-43332 — kernel: thermal: core: Fix thermal zone device registration error path CVE-2026-45861 — kernel: gfs2: Fix slab-use-after-free in qd_put CVE-2026-46076 — kernel: KVM: nSVM: Raise #UD if unhandled VMMCALL isn't intercepted by L1 CVE-2026-46275 — kernel: Bluetooth: hci_uart: fix UAFs and race conditions in close and init paths CVE-2026-46317 — kernel: KVM: arm64: Reassign nested_mmus array behind mmu_lock CVE-2026-52942 — kernel: netfilter: nf_log: validate MAC header was set before dumping it CVE-2026-52986 — kernel: netfilter: nf_conntrack_sip: don't use simple_strtoul CVE-2026-53049 — kernel: gfs2: add some missing log locking CVE-2026-53357 — kernel: Bluetooth: fix UAF in l2cap_sock_cleanup_listen() vs l2cap_conn_del() CVE-2026-63829 — kernel: net: ip_gre: require CAP_NET_ADMIN in the device netns for changelink 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-2026-63993 — kernel: vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu() CVE-2026-63994 — kernel: tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmpv6 CVE-2026-64385 — kernel: Kernel SMB client: Double-free vulnerability allows remote denial of service or privilege escalation 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-2026-72052 — kernel: net: ip6_gre: require CAP_NET_ADMIN in the device netns for changelink CVE-2026-72099 — kernel: dm-integrity: don't increment hash_offset twice CVE-2026-72255 — kernel: netfilter: nf_queue: pin bridge device while NFQUEUE holds fake dst CVE-2026-72289 — kernel: KVM: arm64: vgic: Check the interrupt is still ours before migrating it CVE-2026-74516 — kernel: KVM: SVM: Update x2APIC MSR intercepts if AVIC is inhibited while L2 is active CVE-2026-74569 — kernel: netfilter: nf_conntrack_sip: widen NAT rewrite delta to s32 in sip_help_tcp() 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-2026-80792 — kernel: ipv6: fix use-after-free in ip6_finish_output2() CVE-2026-80921 — kernel: KVM: s390: vsie: zero stale crypto bits CVE-2026-89480 — kernel: nvme-tcp: reject a read that transferred too few bytes CVE-2026-89481 — kernel: nvme-tcp: fix host memory disclosure on R2T for a read command 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

  • Red Hat Enterprise Linux AppStream (v. 9)
  • Red Hat Enterprise Linux BaseOS (v. 9)
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)
  • Red Hat Enterprise Linux Real Time (v. 9)
  • Red Hat Enterprise Linux Real Time for NFV (v. 9)
  • kernel-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-0:5.14.0-687.55.1.el9_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-0:5.14.0-687.55.1.el9_8.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-0:5.14.0-687.55.1.el9_8.src as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-0:5.14.0-687.55.1.el9_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-64k-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-64k-core-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-64k-debug-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-64k-debug-core-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-64k-debug-debuginfo-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • kernel-64k-debug-debuginfo-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-64k-debug-debuginfo-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)
  • kernel-64k-debug-debuginfo-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux Real Time (v. 9)
  • kernel-64k-debug-devel-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • kernel-64k-debug-devel-matched-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • kernel-64k-debug-modules-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-64k-debug-modules-core-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-64k-debug-modules-extra-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-64k-debuginfo-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • kernel-64k-debuginfo-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • kernel-64k-debuginfo-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)
  • kernel-64k-debuginfo-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux Real Time (v. 9)
  • kernel-64k-devel-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • kernel-64k-devel-matched-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • kernel-64k-modules-0:5.14.0-687.55.1.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • +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 don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. 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: 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 `dm-integrity` kernel module from loading. Create a file named `/etc/modprobe.d/disable-dm-integrity.conf` with the following content: `blacklist dm_integrity` `install dm_integrity /bin/true` After creating the file, regenerate the initramfs and reboot the system for the changes to take effect. Disabling this module may impact systems relying on device-mapper integrity features. A system reboot is required for the changes to be applied. 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 nvme-tcp kernel module from loading if NVMe-over-TCP storage connectivity is not required on the host: 1. Create a configuration file to blacklist the driver and prevent it from loading: # echo "install nvme-tcp /bin/true" > /etc/modprobe.d/nvme-tcp.conf # echo "blacklist nvme-tcp" >> /etc/modprobe.d/nvme-tcp.conf 2. If the module is currently loaded, unload it: # modprobe -r nvme-tcp Caveats: Applying this operational workaround disables all NVMe-over-TCP initiator functionality and prevents connections to NVMe-oF network storage fabrics. If the module is actively in use by mounted file systems or active block devices, it cannot be safely unloaded at runtime without first unmounting those targets, and a system reboot may be required to cleanly unload the driver. Workaround: Prevent the nvme-tcp kernel module from loading if NVMe over TCP storage is not required on the system. 1. Add an entry to /etc/modprobe.d to prevent the module from loading: # echo "install nvme-tcp /bin/true" >> /etc/modprobe.d/disable-nvme-tcp.conf 2. If the module is currently loaded and not in use by any storage target, unload it: # modprobe -r nvme-tcp Caveats: Disabling this module prevents the system from connecting to NVMe over TCP block storage devices. Warning: Do not attempt to unload this module if active NVMe over TCP storage is mounted or in use, as doing so will cause I/O failure and potential data loss. If the module cannot be cleanly unloaded, a system restart is required for the change to take full effect. Additionally, restrict NVMe-oF connections to verified, trusted storage targets over isolated or encrypted network fabrics. 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 (41)