A grub2, mokutil, shim, and shim-unsigned-x64 security update has been released for Red Hat Enterprise Linux 8.2.

RHSA-2022:5100-01: Important: grub2, mokutil, shim, and shim-unsigned-x64 security update

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Red Hat Security Advisory

Synopsis: Important: grub2, mokutil, shim, and shim-unsigned-x64 security update
Advisory ID: RHSA-2022:5100-01
Product: Red Hat Enterprise Linux
Advisory URL:   https://access.redhat.com/errata/RHSA-2022:5100
Issue date: 2022-06-16
CVE Names: CVE-2021-3695 CVE-2021-3696 CVE-2021-3697
CVE-2022-28733 CVE-2022-28734 CVE-2022-28735
CVE-2022-28736 CVE-2022-28737
=====================================================================

1. Summary:

An update for grub2, mokutil, shim, and shim-unsigned-x64 is now available
for Red Hat Enterprise Linux 8.2 Extended Update Support.

Red Hat Product Security has rated this update as having a security impact
of Important. A Common Vulnerability Scoring System (CVSS) base score,
which gives a detailed severity rating, is available for each vulnerability
from the CVE link(s) in the References section.

2. Relevant releases/architectures:

Red Hat CodeReady Linux Builder EUS (v. 8.2) - x86_64
Red Hat Enterprise Linux BaseOS EUS (v. 8.2) - aarch64, noarch, ppc64le, x86_64

3. Description:

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.

4. Solution:

For details on how to apply this update, which includes the changes
described in this advisory, refer to:

  https://access.redhat.com/articles/11258

5. Bugs fixed (  https://bugzilla.redhat.com/):

1991685 - CVE-2021-3695 grub2: Crafted PNG grayscale images may lead to out-of-bounds write in heap
1991686 - CVE-2021-3696 grub2: Crafted PNG image may lead to out-of-bound write during huffman table handling
1991687 - CVE-2021-3697 grub2: Crafted JPEG image can lead to buffer underflow write in the heap
2083339 - CVE-2022-28733 grub2: Integer underflow in grub_net_recv_ip4_packets
2090463 - CVE-2022-28734 grub2: Out-of-bound write when handling split HTTP headers
2090857 - CVE-2022-28735 grub2: shim_lock verifier allows non-kernel files to be loaded
2090899 - CVE-2022-28737 shim: Buffer overflow when loading crafted EFI images
2092613 - CVE-2022-28736 grub2: use-after-free in grub_cmd_chainloader()

6. Package List:

Red Hat Enterprise Linux BaseOS EUS (v. 8.2):

Source:
grub2-2.02-87.el8_2.10.src.rpm
mokutil-0.3.0-9.el8_2.2.src.rpm
shim-15.6-1.el8.src.rpm

aarch64:
grub2-debuginfo-2.02-87.el8_2.10.aarch64.rpm
grub2-debugsource-2.02-87.el8_2.10.aarch64.rpm
grub2-efi-aa64-2.02-87.el8_2.10.aarch64.rpm
grub2-efi-aa64-cdboot-2.02-87.el8_2.10.aarch64.rpm
grub2-tools-2.02-87.el8_2.10.aarch64.rpm
grub2-tools-debuginfo-2.02-87.el8_2.10.aarch64.rpm
grub2-tools-extra-2.02-87.el8_2.10.aarch64.rpm
grub2-tools-extra-debuginfo-2.02-87.el8_2.10.aarch64.rpm
grub2-tools-minimal-2.02-87.el8_2.10.aarch64.rpm
grub2-tools-minimal-debuginfo-2.02-87.el8_2.10.aarch64.rpm
mokutil-0.3.0-9.el8_2.2.aarch64.rpm
mokutil-debuginfo-0.3.0-9.el8_2.2.aarch64.rpm
mokutil-debugsource-0.3.0-9.el8_2.2.aarch64.rpm
shim-aa64-15.6-1.el8.aarch64.rpm

noarch:
grub2-common-2.02-87.el8_2.10.noarch.rpm
grub2-efi-aa64-modules-2.02-87.el8_2.10.noarch.rpm
grub2-efi-ia32-modules-2.02-87.el8_2.10.noarch.rpm
grub2-efi-x64-modules-2.02-87.el8_2.10.noarch.rpm
grub2-pc-modules-2.02-87.el8_2.10.noarch.rpm
grub2-ppc64le-modules-2.02-87.el8_2.10.noarch.rpm

ppc64le:
grub2-debuginfo-2.02-87.el8_2.10.ppc64le.rpm
grub2-debugsource-2.02-87.el8_2.10.ppc64le.rpm
grub2-ppc64le-2.02-87.el8_2.10.ppc64le.rpm
grub2-tools-2.02-87.el8_2.10.ppc64le.rpm
grub2-tools-debuginfo-2.02-87.el8_2.10.ppc64le.rpm
grub2-tools-extra-2.02-87.el8_2.10.ppc64le.rpm
grub2-tools-extra-debuginfo-2.02-87.el8_2.10.ppc64le.rpm
grub2-tools-minimal-2.02-87.el8_2.10.ppc64le.rpm
grub2-tools-minimal-debuginfo-2.02-87.el8_2.10.ppc64le.rpm

x86_64:
grub2-debuginfo-2.02-87.el8_2.10.x86_64.rpm
grub2-debugsource-2.02-87.el8_2.10.x86_64.rpm
grub2-efi-ia32-2.02-87.el8_2.10.x86_64.rpm
grub2-efi-ia32-cdboot-2.02-87.el8_2.10.x86_64.rpm
grub2-efi-x64-2.02-87.el8_2.10.x86_64.rpm
grub2-efi-x64-cdboot-2.02-87.el8_2.10.x86_64.rpm
grub2-pc-2.02-87.el8_2.10.x86_64.rpm
grub2-tools-2.02-87.el8_2.10.x86_64.rpm
grub2-tools-debuginfo-2.02-87.el8_2.10.x86_64.rpm
grub2-tools-efi-2.02-87.el8_2.10.x86_64.rpm
grub2-tools-efi-debuginfo-2.02-87.el8_2.10.x86_64.rpm
grub2-tools-extra-2.02-87.el8_2.10.x86_64.rpm
grub2-tools-extra-debuginfo-2.02-87.el8_2.10.x86_64.rpm
grub2-tools-minimal-2.02-87.el8_2.10.x86_64.rpm
grub2-tools-minimal-debuginfo-2.02-87.el8_2.10.x86_64.rpm
mokutil-0.3.0-9.el8_2.2.x86_64.rpm
mokutil-debuginfo-0.3.0-9.el8_2.2.x86_64.rpm
mokutil-debugsource-0.3.0-9.el8_2.2.x86_64.rpm
shim-ia32-15.6-1.el8.x86_64.rpm
shim-x64-15.6-1.el8.x86_64.rpm

Red Hat CodeReady Linux Builder EUS (v. 8.2):

Source:
shim-unsigned-x64-15.6-1.el8.src.rpm

x86_64:
shim-unsigned-x64-15.6-1.el8.x86_64.rpm

These packages are GPG signed by Red Hat for security. Our key and
details on how to verify the signature are available from
  https://access.redhat.com/security/team/key/

7. References:

  https://access.redhat.com/security/cve/CVE-2021-3695
  https://access.redhat.com/security/cve/CVE-2021-3696
  https://access.redhat.com/security/cve/CVE-2021-3697
  https://access.redhat.com/security/cve/CVE-2022-28733
  https://access.redhat.com/security/cve/CVE-2022-28734
  https://access.redhat.com/security/cve/CVE-2022-28735
  https://access.redhat.com/security/cve/CVE-2022-28736
  https://access.redhat.com/security/cve/CVE-2022-28737
  https://access.redhat.com/security/updates/classification/#important

8. Contact:

The Red Hat security contact is . More contact
details at   https://access.redhat.com/security/team/contact/

Copyright 2022 Red Hat, Inc.