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High ALSA-2026:26428 8 CVEs

Important: kernel-rt security update

Published Jun 16, 2026 · Updated Oct 29, 2026

Ecosystem: AlmaLinux

Summary

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: mptcp: fix slab-use-after-free in __inet_lookup_established (CVE-2026-31669)
* kernel: xen/privcmd: fix double free via VMA splitting (CVE-2026-31787)
* kernel: Buffer overflow in drivers/xen/sys-hypervisor.c (CVE-2026-31786)
* kernel: wifi: brcmfmac: validate bsscfg indices in IF events (CVE-2026-43110)
* kernel: netfilter: flowtable: strictly check for maximum number of actions (CVE-2026-43329)
* kernel: Bluetooth: hci_event: fix potential UAF in SSP passkey handlers (CVE-2026-46056)
* kernel: wifi: mac80211: drop stray 'static' from fast-RX rx_result (CVE-2026-46152)
* kernel: wifi: mac80211: remove station if connection prep fails (CVE-2026-46125)

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.

Fixed packages 10

ReleasePackageFixed in
AlmaLinux · 8 kernel-rt 4.18.0-553.134.1.rt7.475.el8_10
AlmaLinux · 8 kernel-rt-core 4.18.0-553.134.1.rt7.475.el8_10
AlmaLinux · 8 kernel-rt-debug 4.18.0-553.134.1.rt7.475.el8_10
AlmaLinux · 8 kernel-rt-debug-core 4.18.0-553.134.1.rt7.475.el8_10
AlmaLinux · 8 kernel-rt-debug-devel 4.18.0-553.134.1.rt7.475.el8_10
AlmaLinux · 8 kernel-rt-debug-modules 4.18.0-553.134.1.rt7.475.el8_10
AlmaLinux · 8 kernel-rt-debug-modules-extra 4.18.0-553.134.1.rt7.475.el8_10
AlmaLinux · 8 kernel-rt-devel 4.18.0-553.134.1.rt7.475.el8_10
AlmaLinux · 8 kernel-rt-modules 4.18.0-553.134.1.rt7.475.el8_10
AlmaLinux · 8 kernel-rt-modules-extra 4.18.0-553.134.1.rt7.475.el8_10

Vulnerabilities 8

  • Critical 9.8
    CVE-2026-31669

    mptcp: fix slab-use-after-free in __inet_lookup_established

    In the Linux kernel, the following vulnerability has been resolved: mptcp: fix slab-use-after-free in __inet_lookup_established The ehash table lookups are lockless and rely on SLAB_TYPESAFE_BY_RCU to guarantee socket memory stability during RCU read-side cri…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  • High 8.8
    CVE-2026-43110

    wifi: brcmfmac: validate bsscfg indices in IF events

    In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: validate bsscfg indices in IF events brcmf_fweh_handle_if_event() validates the firmware-provided interface index before it touches drvr->iflist[], but it still uses the raw b…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • High 8.8
    CVE-2026-46056

    Bluetooth: hci_event: fix potential UAF in SSP passkey handlers

    In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_event: fix potential UAF in SSP passkey handlers hci_conn lookup and field access must be covered by hdev lock in hci_user_passkey_notify_evt() and hci_keypress_notify_evt(), o…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  • High 8.8
    CVE-2026-46125

    wifi: mac80211: remove station if connection prep fails

    In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: remove station if connection prep fails If connection preparation fails for MLO connections, then the interface is completely reset to non-MLD. In this case, we must not keep …

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  • High 8.8
    CVE-2026-46152

    wifi: mac80211: drop stray 'static' from fast-RX rx_result

    In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: drop stray 'static' from fast-RX rx_result ieee80211_invoke_fast_rx() is documented as safe for parallel RX, but its per-invocation rx_result is declared static. Concurrent ca…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  • High 7.8
    CVE-2026-31786

    Buffer overflow in drivers/xen/sys-hypervisor.c

    In the Linux kernel, the following vulnerability has been resolved: Buffer overflow in drivers/xen/sys-hypervisor.c The build id returned by HYPERVISOR_xen_version(XENVER_build_id) is neither NUL terminated nor a string. The first causes a buffer overflow as …

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • High 7.8
    CVE-2026-43329

    netfilter: flowtable: strictly check for maximum number of actions

    In the Linux kernel, the following vulnerability has been resolved: netfilter: flowtable: strictly check for maximum number of actions The maximum number of flowtable hardware offload actions in IPv6 is: * ethernet mangling (4 payload actions, 2 for each ethe…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  • Unscored —
    CVE-2026-31787 Public exploit

    xen/privcmd: fix double free via VMA splitting

    In the Linux kernel, the following vulnerability has been resolved: xen/privcmd: fix double free via VMA splitting privcmd_vm_ops defines .close (privcmd_close), but neither .may_split nor .open. When userspace does a partial munmap() on a privcmd mapping, th…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu

References

  • report
    https://access.redhat.com/security/cve/CVE-2026-31669
  • report
    https://access.redhat.com/security/cve/CVE-2026-31786
  • report
    https://access.redhat.com/security/cve/CVE-2026-31787
  • report
    https://access.redhat.com/security/cve/CVE-2026-43110
  • report
    https://access.redhat.com/security/cve/CVE-2026-43329
  • report
    https://access.redhat.com/security/cve/CVE-2026-46056
  • report
    https://access.redhat.com/security/cve/CVE-2026-46125
  • report
    https://access.redhat.com/security/cve/CVE-2026-46152
  • report
    https://bugzilla.redhat.com/2461503
  • report
    https://bugzilla.redhat.com/2464092
  • report
    https://bugzilla.redhat.com/2464096
  • report
    https://bugzilla.redhat.com/2467014
  • report
    https://bugzilla.redhat.com/2468124
  • report
    https://bugzilla.redhat.com/2482181
  • report
    https://bugzilla.redhat.com/2482563
  • report
    https://bugzilla.redhat.com/2482608
  • advisory
    https://errata.almalinux.org/8/ALSA-2026-26428.html