Security update for shim

SUSE Security Update: Security update for shim
Announcement ID: SUSE-SU-2020:2629-1
Rating: moderate
References: #1113225 #1121268 #1153953 #1168104 #1168994 #1173411 #1174320 #1175626 #1175656
Cross-References:CVE-2020-10713
Affected Products:
  • SUSE Linux Enterprise Module for Basesystem 15-SP2
  • SUSE Linux Enterprise Module for Basesystem 15-SP1

An update that solves one vulnerability and has 8 fixes is now available.

Description:

This update for shim fixes the following issues:
This update addresses the "BootHole" security issue (master CVE CVE-2020-10713), by disallowing binaries signed by the previous SUSE UEFI signing key from booting.
This update should only be installed after updates of grub2, the Linux kernel and (if used) Xen from July / August 2020 are applied.

Changes:
Use vendor-dbx to block old SUSE/openSUSE signkeys (bsc#1168994)

  • Add dbx-cert.tar.xz which contains the certificates to block and a script, generate-vendor-dbx.sh, to generate vendor-dbx.bin
  • Add vendor-dbx.bin as the vendor dbx to block unwanted keys


  • Update the path to grub-tpm.efi in shim-install (bsc#1174320)
  • Only check EFI variable copying when Secure Boot is enabled (bsc#1173411)
  • Use the full path of efibootmgr to avoid errors when invoking shim-install from packagekitd (bsc#1168104)
  • shim-install: add check for btrfs is used as root file system to enable relative path lookup for file. (bsc#1153953)
  • shim-install: install MokManager to \EFI\boot to process the pending MOK request (bsc#1175626, bsc#1175656)

Patch Instructions:

To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Alternatively you can run the command listed for your product:

  • SUSE Linux Enterprise Module for Basesystem 15-SP2:
    zypper in -t patch SUSE-SLE-Module-Basesystem-15-SP2-2020-2629=1
  • SUSE Linux Enterprise Module for Basesystem 15-SP1:
    zypper in -t patch SUSE-SLE-Module-Basesystem-15-SP1-2020-2629=1

Package List:

  • SUSE Linux Enterprise Module for Basesystem 15-SP2 (x86_64):
    • shim-15+git47-3.8.1
    • shim-debuginfo-15+git47-3.8.1
    • shim-debugsource-15+git47-3.8.1
  • SUSE Linux Enterprise Module for Basesystem 15-SP1 (x86_64):
    • shim-15+git47-3.8.1
    • shim-debuginfo-15+git47-3.8.1
    • shim-debugsource-15+git47-3.8.1

References: