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Red Hat Product Errata RHSA-2021:1734 - Security Advisory
Issued:
2021-05-18
Updated:
2021-05-18

RHSA-2021:1734 - Security Advisory

  • Overview
  • Updated Packages

Synopsis

Moderate: shim security update

Type/Severity

Security Advisory: Moderate

Red Hat Insights patch analysis

Identify and remediate systems affected by this advisory.

View affected systems

Topic

An update for shim, shim-unsigned-aarch64, and shim-unsigned-x64 is now available for Red Hat Enterprise Linux 8.

Red Hat Product Security has rated this update as having a security impact of Moderate. 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.

Description

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.

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

Affected Products

  • Red Hat Enterprise Linux for x86_64 8 x86_64
  • Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.8 x86_64
  • Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.6 x86_64
  • Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.4 x86_64
  • Red Hat Enterprise Linux Server - AUS 8.6 x86_64
  • Red Hat Enterprise Linux Server - AUS 8.4 x86_64
  • Red Hat Enterprise Linux Server - TUS 8.8 x86_64
  • Red Hat Enterprise Linux Server - TUS 8.6 x86_64
  • Red Hat Enterprise Linux Server - TUS 8.4 x86_64
  • Red Hat Enterprise Linux for ARM 64 8 aarch64
  • Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.8 aarch64
  • Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.6 aarch64
  • Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.4 aarch64
  • Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.8 x86_64
  • Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.6 x86_64
  • Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.4 x86_64
  • Red Hat CodeReady Linux Builder for x86_64 8 x86_64
  • Red Hat CodeReady Linux Builder for ARM 64 8 aarch64
  • Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 8.8 x86_64
  • Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 8.6 x86_64
  • Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 8.4 x86_64
  • Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 8.8 aarch64
  • Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 8.6 aarch64
  • Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 8.4 aarch64

Fixes

  • BZ - 1873150 - CVE-2020-14372 grub2: acpi command allows privileged user to load crafted ACPI tables when Secure Boot is enabled
  • BZ - 1879577 - CVE-2020-25632 grub2: Use-after-free in rmmod command
  • BZ - 1886936 - CVE-2020-25647 grub2: Out-of-bounds write in grub_usb_device_initialize()
  • BZ - 1899966 - CVE-2020-27749 grub2: Stack buffer overflow in grub_parser_split_cmdline()
  • BZ - 1900698 - CVE-2020-27779 grub2: cutmem command allows privileged user to remove memory regions when Secure Boot is enabled
  • BZ - 1924696 - CVE-2021-20225 grub2: Heap out-of-bounds write in short form option parser
  • BZ - 1926263 - CVE-2021-20233 grub2: Heap out-of-bounds write due to miscalculation of space required for quoting

CVEs

  • CVE-2020-14372
  • CVE-2020-25632
  • CVE-2020-25647
  • CVE-2020-27749
  • CVE-2020-27779
  • CVE-2021-20225
  • CVE-2021-20233

References

  • 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/
Note: More recent versions of these packages may be available. Click a package name for more details.

Red Hat Enterprise Linux for x86_64 8

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
x86_64
shim-ia32-15.4-2.el8_1.x86_64.rpm SHA-256: 540fc6f47a51b210369e85517f70aba9e91b84acbc423f0c70f7653d1f357d71
shim-x64-15.4-2.el8_1.x86_64.rpm SHA-256: c5fb6e950b077770f207e29bb31e408739272058892ba8bf0066a9483575d306

Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.8

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
x86_64
shim-ia32-15.4-2.el8_1.x86_64.rpm SHA-256: 540fc6f47a51b210369e85517f70aba9e91b84acbc423f0c70f7653d1f357d71
shim-x64-15.4-2.el8_1.x86_64.rpm SHA-256: c5fb6e950b077770f207e29bb31e408739272058892ba8bf0066a9483575d306

Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.6

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
x86_64
shim-ia32-15.4-2.el8_1.x86_64.rpm SHA-256: 540fc6f47a51b210369e85517f70aba9e91b84acbc423f0c70f7653d1f357d71
shim-x64-15.4-2.el8_1.x86_64.rpm SHA-256: c5fb6e950b077770f207e29bb31e408739272058892ba8bf0066a9483575d306

Red Hat Enterprise Linux for x86_64 - Extended Update Support 8.4

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
x86_64
shim-ia32-15.4-2.el8_1.x86_64.rpm SHA-256: 540fc6f47a51b210369e85517f70aba9e91b84acbc423f0c70f7653d1f357d71
shim-x64-15.4-2.el8_1.x86_64.rpm SHA-256: c5fb6e950b077770f207e29bb31e408739272058892ba8bf0066a9483575d306

Red Hat Enterprise Linux Server - AUS 8.6

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
x86_64
shim-ia32-15.4-2.el8_1.x86_64.rpm SHA-256: 540fc6f47a51b210369e85517f70aba9e91b84acbc423f0c70f7653d1f357d71
shim-x64-15.4-2.el8_1.x86_64.rpm SHA-256: c5fb6e950b077770f207e29bb31e408739272058892ba8bf0066a9483575d306

Red Hat Enterprise Linux Server - AUS 8.4

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
x86_64
shim-ia32-15.4-2.el8_1.x86_64.rpm SHA-256: 540fc6f47a51b210369e85517f70aba9e91b84acbc423f0c70f7653d1f357d71
shim-x64-15.4-2.el8_1.x86_64.rpm SHA-256: c5fb6e950b077770f207e29bb31e408739272058892ba8bf0066a9483575d306

Red Hat Enterprise Linux Server - TUS 8.8

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
x86_64
shim-ia32-15.4-2.el8_1.x86_64.rpm SHA-256: 540fc6f47a51b210369e85517f70aba9e91b84acbc423f0c70f7653d1f357d71
shim-x64-15.4-2.el8_1.x86_64.rpm SHA-256: c5fb6e950b077770f207e29bb31e408739272058892ba8bf0066a9483575d306

Red Hat Enterprise Linux Server - TUS 8.6

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
x86_64
shim-ia32-15.4-2.el8_1.x86_64.rpm SHA-256: 540fc6f47a51b210369e85517f70aba9e91b84acbc423f0c70f7653d1f357d71
shim-x64-15.4-2.el8_1.x86_64.rpm SHA-256: c5fb6e950b077770f207e29bb31e408739272058892ba8bf0066a9483575d306

Red Hat Enterprise Linux Server - TUS 8.4

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
x86_64
shim-ia32-15.4-2.el8_1.x86_64.rpm SHA-256: 540fc6f47a51b210369e85517f70aba9e91b84acbc423f0c70f7653d1f357d71
shim-x64-15.4-2.el8_1.x86_64.rpm SHA-256: c5fb6e950b077770f207e29bb31e408739272058892ba8bf0066a9483575d306

Red Hat Enterprise Linux for ARM 64 8

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
aarch64
shim-aa64-15.4-2.el8_1.aarch64.rpm SHA-256: b97af00f72ced6bb75ac2c5eb1100b4a39fea8867d68e6d633ea89f187689439

Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.8

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
aarch64
shim-aa64-15.4-2.el8_1.aarch64.rpm SHA-256: b97af00f72ced6bb75ac2c5eb1100b4a39fea8867d68e6d633ea89f187689439

Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.6

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
aarch64
shim-aa64-15.4-2.el8_1.aarch64.rpm SHA-256: b97af00f72ced6bb75ac2c5eb1100b4a39fea8867d68e6d633ea89f187689439

Red Hat Enterprise Linux for ARM 64 - Extended Update Support 8.4

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
aarch64
shim-aa64-15.4-2.el8_1.aarch64.rpm SHA-256: b97af00f72ced6bb75ac2c5eb1100b4a39fea8867d68e6d633ea89f187689439

Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.8

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
x86_64
shim-ia32-15.4-2.el8_1.x86_64.rpm SHA-256: 540fc6f47a51b210369e85517f70aba9e91b84acbc423f0c70f7653d1f357d71
shim-x64-15.4-2.el8_1.x86_64.rpm SHA-256: c5fb6e950b077770f207e29bb31e408739272058892ba8bf0066a9483575d306

Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.6

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
x86_64
shim-ia32-15.4-2.el8_1.x86_64.rpm SHA-256: 540fc6f47a51b210369e85517f70aba9e91b84acbc423f0c70f7653d1f357d71
shim-x64-15.4-2.el8_1.x86_64.rpm SHA-256: c5fb6e950b077770f207e29bb31e408739272058892ba8bf0066a9483575d306

Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 8.4

SRPM
shim-15.4-2.el8_1.src.rpm SHA-256: 3bfc26de867105a4c11b7ad56cd82b1d649f45b5d6d51ad2b1474acd46c624f0
x86_64
shim-ia32-15.4-2.el8_1.x86_64.rpm SHA-256: 540fc6f47a51b210369e85517f70aba9e91b84acbc423f0c70f7653d1f357d71
shim-x64-15.4-2.el8_1.x86_64.rpm SHA-256: c5fb6e950b077770f207e29bb31e408739272058892ba8bf0066a9483575d306

Red Hat CodeReady Linux Builder for x86_64 8

SRPM
shim-unsigned-x64-15.4-4.el8_1.src.rpm SHA-256: f242ffa36144ce21319270006d494640f8962b80bf8817eb681296432e99e8d7
x86_64
shim-unsigned-x64-15.4-4.el8_1.x86_64.rpm SHA-256: 9b3ed1bb26663c75308ce54966af6626a8597f224b0dd927c32a7e2655bd218b

Red Hat CodeReady Linux Builder for ARM 64 8

SRPM
shim-unsigned-aarch64-15-7.el8_1.src.rpm SHA-256: f1ee585a3fcf0b8a44808243839d7a2a9643e3dcb46d12dc0cfd32d7d2f66888
aarch64
shim-unsigned-aarch64-15-7.el8_1.aarch64.rpm SHA-256: 426b65bdbc5e280671385e544201edddff179aab64a77bfc0c52f4cfe6eb24fd

Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 8.8

SRPM
shim-unsigned-x64-15.4-4.el8_1.src.rpm SHA-256: f242ffa36144ce21319270006d494640f8962b80bf8817eb681296432e99e8d7
x86_64
shim-unsigned-x64-15.4-4.el8_1.x86_64.rpm SHA-256: 9b3ed1bb26663c75308ce54966af6626a8597f224b0dd927c32a7e2655bd218b

Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 8.6

SRPM
shim-unsigned-x64-15.4-4.el8_1.src.rpm SHA-256: f242ffa36144ce21319270006d494640f8962b80bf8817eb681296432e99e8d7
x86_64
shim-unsigned-x64-15.4-4.el8_1.x86_64.rpm SHA-256: 9b3ed1bb26663c75308ce54966af6626a8597f224b0dd927c32a7e2655bd218b

Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 8.4

SRPM
shim-unsigned-x64-15.4-4.el8_1.src.rpm SHA-256: f242ffa36144ce21319270006d494640f8962b80bf8817eb681296432e99e8d7
x86_64
shim-unsigned-x64-15.4-4.el8_1.x86_64.rpm SHA-256: 9b3ed1bb26663c75308ce54966af6626a8597f224b0dd927c32a7e2655bd218b

Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 8.8

SRPM
shim-unsigned-aarch64-15-7.el8_1.src.rpm SHA-256: f1ee585a3fcf0b8a44808243839d7a2a9643e3dcb46d12dc0cfd32d7d2f66888
aarch64
shim-unsigned-aarch64-15-7.el8_1.aarch64.rpm SHA-256: 426b65bdbc5e280671385e544201edddff179aab64a77bfc0c52f4cfe6eb24fd

Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 8.6

SRPM
shim-unsigned-aarch64-15-7.el8_1.src.rpm SHA-256: f1ee585a3fcf0b8a44808243839d7a2a9643e3dcb46d12dc0cfd32d7d2f66888
aarch64
shim-unsigned-aarch64-15-7.el8_1.aarch64.rpm SHA-256: 426b65bdbc5e280671385e544201edddff179aab64a77bfc0c52f4cfe6eb24fd

Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 8.4

SRPM
shim-unsigned-aarch64-15-7.el8_1.src.rpm SHA-256: f1ee585a3fcf0b8a44808243839d7a2a9643e3dcb46d12dc0cfd32d7d2f66888
aarch64
shim-unsigned-aarch64-15-7.el8_1.aarch64.rpm SHA-256: 426b65bdbc5e280671385e544201edddff179aab64a77bfc0c52f4cfe6eb24fd

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

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