Red Hat Security Advisory: kernel security update

Fixed packages 124

Vulnerabilities 5

• High 8.8
  CVE-2026-64561 Public exploit

  KVM: x86: Check for invalid/obsolete root *after* making MMU pages available

  In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Check for invalid/obsolete root *after* making MMU pages available Check for a "stale" page fault, i.e. for an invalid and/or obsolete root, after making MMU pages available for the…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Aug 4, 2026
• High 8.8
  CVE-2026-64562

  KVM: nVMX: Hide shadow VMCS right after VMCLEAR

  In the Linux kernel, the following vulnerability has been resolved: KVM: nVMX: Hide shadow VMCS right after VMCLEAR free_nested() frees the shadow VMCS while vmcs01 still points to it. But because it is asynchronous with respect to loaded_vmcs_clear(), the vC…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Aug 4, 2026
• High 7.9
  CVE-2025-40026

  KVM: x86: Don't (re)check L1 intercepts when completing userspace I/O

  In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Don't (re)check L1 intercepts when completing userspace I/O When completing emulation of instruction that generated a userspace exit for I/O, don't recheck L1 intercepts as KVM has …

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  Oct 28, 2025
• High 7.8
  CVE-2026-52923 Public exploit

  ipc: limit next_id allocation to the valid ID range

  In the Linux kernel, the following vulnerability has been resolved: ipc: limit next_id allocation to the valid ID range The checkpoint/restore sysctl path can request the next SysV IPC id through ids->next_id. ipc_idr_alloc() currently forwards that request t…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Jun 24, 2026
• 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
  Apr 30, 2026

References

• article
  https://access.redhat.com/security/updates/classification/#important
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2406712
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2464092
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2492094
• advisory
  https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_48386.json
• report
  https://access.redhat.com/security/cve/CVE-2025-40026
• advisory
  https://www.cve.org/CVERecord?id=CVE-2025-40026
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2025-40026
• article
  https://lore.kernel.org/linux-cve-announce/2025102841-CVE-2025-40026-760b@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-31787
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-31787
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-31787
• article
  https://lore.kernel.org/linux-cve-announce/2026043034-CVE-2026-31787-f6cc@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-52923
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-52923
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-52923
• article
  https://lore.kernel.org/linux-cve-announce/2026062431-CVE-2026-52923-35fb@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-64561
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2510891
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-64561
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-64561
• article
  https://lore.kernel.org/linux-cve-announce/2026080401-CVE-2026-64561-d0d4@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-64562
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2510894
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-64562
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-64562
• article
  https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-64562.mbox