Issued:
2024-04-18
Updated:
2024-04-18

RHSA-2024:1873 - Important: shim security update

Synopsis

Important: shim security update

Type/Severity

Security Advisory Important

Topic

An update for shim is now available for Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support, E4S Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions, and Red Hat Enterprise Linux 8.4 Telecommunications Update Service.

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.

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):

  • shim: RCE in http boot support may lead to Secure Boot bypass (CVE-2023-40547)

  • shim: Interger overflow leads to heap buffer overflow in verify_sbat_section on 32-bits systems (CVE-2023-40548)

  • shim: Out-of-bounds read printing error messages (CVE-2023-40546)

  • shim: Out-of-bounds read in verify_buffer_authenticode() malformed PE file (CVE-2023-40549)

  • shim: Out-of-bound read in verify_buffer_sbat() (CVE-2023-40550)

  • shim: out of bounds read when parsing MZ binaries (CVE-2023-40551)

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.

Solution

For details on how to apply this update, refer to:

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

Affected Products

ProductVersionArch
Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions8.4x86_64
Red Hat Enterprise Linux for x86_64 - Extended Update Support Extension8.4x86_64
Red Hat Enterprise Linux Server - TUS8.4x86_64
Red Hat Enterprise Linux Server - AUS8.4x86_64

Updated Packages

  • shim-ia32-15.8-2.el8_4.x86_64.rpm
  • shim-15.8-2.el8_4.src.rpm
  • shim-x64-15.8-2.el8_4.x86_64.rpm

Fixes

CVEs

References

Additional information