Rapid7 Vulnerability & Exploit Database

Centos Linux: CVE-2021-3695: Important: grub2, mokutil, shim, and shim-unsigned-x64 security update (Multiple Advisories)

Back to Search

Centos Linux: CVE-2021-3695: Important: grub2, mokutil, shim, and shim-unsigned-x64 security update (Multiple Advisories)

Severity
4
CVSS
(AV:L/AC:M/Au:N/C:P/I:P/A:P)
Published
06/16/2022
Created
06/18/2022
Added
06/17/2022
Modified
07/18/2022

Description

A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12.

Solution(s)

  • centos-upgrade-grub2-common
  • centos-upgrade-grub2-debuginfo
  • centos-upgrade-grub2-debugsource
  • centos-upgrade-grub2-efi-aa64-modules
  • centos-upgrade-grub2-efi-ia32
  • centos-upgrade-grub2-efi-ia32-cdboot
  • centos-upgrade-grub2-efi-ia32-modules
  • centos-upgrade-grub2-efi-x64
  • centos-upgrade-grub2-efi-x64-cdboot
  • centos-upgrade-grub2-efi-x64-modules
  • centos-upgrade-grub2-emu-debuginfo
  • centos-upgrade-grub2-pc
  • centos-upgrade-grub2-pc-modules
  • centos-upgrade-grub2-ppc64le-modules
  • centos-upgrade-grub2-tools
  • centos-upgrade-grub2-tools-debuginfo
  • centos-upgrade-grub2-tools-efi
  • centos-upgrade-grub2-tools-efi-debuginfo
  • centos-upgrade-grub2-tools-extra
  • centos-upgrade-grub2-tools-extra-debuginfo
  • centos-upgrade-grub2-tools-minimal
  • centos-upgrade-grub2-tools-minimal-debuginfo
  • centos-upgrade-mokutil
  • centos-upgrade-mokutil-debuginfo
  • centos-upgrade-mokutil-debugsource
  • centos-upgrade-shim-ia32
  • centos-upgrade-shim-x64

With Rapid7 live dashboards, I have a clear view of all the assets on my network, which ones can be exploited, and what I need to do in order to reduce the risk in my environment in real-time. No other tool gives us that kind of value and insight.

– Scott Cheney, Manager of Information Security, Sierra View Medical Center

;