GRUB2 version 2.04 Concurrent Execution using Shared Resource with Improper Synchronization (‘Race Condition’) Vulnerability


Integer overflows were discovered in the functions grub_cmd_initrd and grub_initrd_init in the efilinux component of GRUB2, as shipped in Debian, Red Hat, and Ubuntu (the functionality is not included in GRUB2 upstream), leading to a heap-based buffer overflow.


The information has been provided by Daniel Kiper

The original article can be found at:


These could be triggered by an extremely large number of arguments to the initrd command on 32-bit architectures, or a crafted filesystem with very large files on any architecture. An attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. This issue affects GRUB2 version 2.04 and prior versions.


Vulnerable Systems:

GRUB2 version 2.04


CVE Information:



Disclosure Timeline:
Published Date:7/29/2020

Categories: FeaturedNews