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High ALSA-2022:5099 8 CVEs

Important: grub2, mokutil, shim, and shim-unsigned-x64 security update

Published Jun 16, 2022 · Updated Oct 29, 2026

Summary

The grub2 packages provide version 2 of the Grand Unified Boot Loader (GRUB), a highly configurable and customizable boot loader with modular architecture. The packages support a variety of kernel formats, file systems, computer architectures, and hardware devices.
The shim package contains a first-stage UEFI boot loader that handles chaining to a trusted full boot loader under secure boot environments.
Security Fix(es):
* grub2: Integer underflow in grub_net_recv_ip4_packets (CVE-2022-28733)
* grub2: Crafted PNG grayscale images may lead to out-of-bounds write in heap (CVE-2021-3695)
* grub2: Crafted PNG image may lead to out-of-bound write during huffman table handling (CVE-2021-3696)
* grub2: Crafted JPEG image can lead to buffer underflow write in the heap (CVE-2021-3697)
* grub2: Out-of-bound write when handling split HTTP headers (CVE-2022-28734)
* grub2: shim_lock verifier allows non-kernel files to be loaded (CVE-2022-28735)
* grub2: use-after-free in grub_cmd_chainloader() (CVE-2022-28736)
* shim: Buffer overflow when loading crafted EFI images (CVE-2022-28737)
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 18

ReleasePackageFixed in
AlmaLinux · 9 grub2-common 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-efi-aa64 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-efi-aa64-cdboot 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-efi-aa64-modules 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-efi-x64 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-efi-x64-cdboot 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-efi-x64-modules 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-pc 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-pc-modules 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-ppc64le 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-ppc64le-modules 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-tools 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-tools-efi 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-tools-extra 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 grub2-tools-minimal 1:2.06-27.el9_0.7.alma
AlmaLinux · 9 shim-aa64 15.6-1.el9.alma
AlmaLinux · 9 shim-unsigned-x64 15.6-1.el9.alma
AlmaLinux · 9 shim-x64 15.6-1.el9.alma

Vulnerabilities 8

References

  • report
    https://access.redhat.com/security/cve/CVE-2021-3695
  • report
    https://access.redhat.com/security/cve/CVE-2021-3696
  • report
    https://access.redhat.com/security/cve/CVE-2021-3697
  • report
    https://access.redhat.com/security/cve/CVE-2022-28733
  • report
    https://access.redhat.com/security/cve/CVE-2022-28734
  • report
    https://access.redhat.com/security/cve/CVE-2022-28735
  • report
    https://access.redhat.com/security/cve/CVE-2022-28736
  • report
    https://access.redhat.com/security/cve/CVE-2022-28737
  • report
    https://bugzilla.redhat.com/1991685
  • report
    https://bugzilla.redhat.com/1991686
  • report
    https://bugzilla.redhat.com/1991687
  • report
    https://bugzilla.redhat.com/2083339
  • report
    https://bugzilla.redhat.com/2090463
  • report
    https://bugzilla.redhat.com/2090857
  • report
    https://bugzilla.redhat.com/2090899
  • report
    https://bugzilla.redhat.com/2092613
  • advisory
    https://errata.almalinux.org/9/ALSA-2022-5099.html