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Red Hat Enterprise Linux 8: RHSA-2021-1734-01 Moderate Shim Security Update

red hat
Calendar Grey May 18, 2021
Scroller Redhat
Ubuntu Server 22.04 experienced a significant patch release for grub, addressing several critical vulnerabilities.
An update for shim, shim-unsigned-aarch64, and shim-unsigned-x64 is now available for Red Hat Enterprise Linux 8

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

Summary

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: acpi command allows privileged user to load crafted ACPI tables when Secure Boot is enabled (CVE-2020-14372)
* grub2: Use-after-free in rmmod command (CVE-2020-25632)
* grub2: Out-of-bounds write in grub_usb_device_initialize() (CVE-2020-25647)
* grub2: Stack buffer overflow in grub_parser_split_cmdline() (CVE-2020-27749)
* grub2: cutmem command allows privileged user to remove memory regions when Secure Boot is enabled (CVE-2020-27779)
* grub2: Heap out-of-bounds write in short form option parser (CVE-2021-20225)
* grub2: Heap out-of-bounds write due to miscalculation of space required for quoting (CVE-2021-20233)
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.
Additional Changes:
For detailed information on changes in this release, see the Red Hat Enterprise Linux 8.4 Release Notes linked from the References section.

Topics%20covered

Topics Covered

security advisory security update security fix Red Hat Enterprise Linux shim Moderate impact boot loader

References

https://access.redhat.com/security/cve/CVE-2020-14372 https://access.redhat.com/security/cve/CVE-2020-25632 https://access.redhat.com/security/cve/CVE-2020-25647 https://access.redhat.com/security/cve/CVE-2020-27749 https://access.redhat.com/security/cve/CVE-2020-27779 https://access.redhat.com/security/cve/CVE-2021-20225 https://access.redhat.com/security/cve/CVE-2021-20233 https://access.redhat.com/security/updates/classification/#moderate https://access.redhat.com/security/vulnerabilities/RHSB-2021-003 https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/8.4_release_notes/

Package List

Red Hat Enterprise Linux BaseOS (v. 8):
Source: shim-15.4-2.el8_1.src.rpm
aarch64: shim-aa64-15.4-2.el8_1.aarch64.rpm
x86_64: shim-ia32-15.4-2.el8_1.x86_64.rpm shim-x64-15.4-2.el8_1.x86_64.rpm
Red Hat CodeReady Linux Builder (v. 8):
Source: shim-unsigned-aarch64-15-7.el8_1.src.rpm shim-unsigned-x64-15.4-4.el8_1.src.rpm
aarch64: shim-unsigned-aarch64-15-7.el8_1.aarch64.rpm
x86_64: shim-unsigned-x64-15.4-4.el8_1.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/


Advisory ID: RHSA-2021:1734-01
Product: Red Hat Enterprise Linux
Advisory URL: https://access.redhat.com/errata/RHSA-2021:1734
Issue date: 2021-05-18

Topic

An update for shim, shim-unsigned-aarch64, and shim-unsigned-x64 is nowavailable for Red Hat Enterprise Linux 8.Red Hat Product Security has rated this update as having a security impactof Moderate. A Common Vulnerability Scoring System (CVSS) base score, whichgives a detailed severity rating, is available for each vulnerability fromthe CVE link(s) in the References section.

Topics%20covered

Topics Covered

security advisory security update security fix Red Hat Enterprise Linux shim Moderate impact boot loader

Relevant Releases Architectures

Red Hat CodeReady Linux Builder (v. 8) - aarch64, x86_64

Red Hat Enterprise Linux BaseOS (v. 8) - aarch64, x86_64

Bugs Fixed

1873150 - CVE-2020-14372 grub2: acpi command allows privileged user to load crafted ACPI tables when Secure Boot is enabled

1879577 - CVE-2020-25632 grub2: Use-after-free in rmmod command

1886936 - CVE-2020-25647 grub2: Out-of-bounds write in grub_usb_device_initialize()

1899966 - CVE-2020-27749 grub2: Stack buffer overflow in grub_parser_split_cmdline()

1900698 - CVE-2020-27779 grub2: cutmem command allows privileged user to remove memory regions when Secure Boot is enabled

1924696 - CVE-2021-20225 grub2: Heap out-of-bounds write in short form option parser

1926263 - CVE-2021-20233 grub2: Heap out-of-bounds write due to miscalculation of space required for quoting

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