GRUB2 contains a race condition in grub_script_function_create() leading to a use-after-free vulnerability which can be triggered by redefining a function whilst the same function is already executing, leading to arbitrary code execution and secure boot restriction bypass. This issue affects GRUB2 version 2.04 and prior versions.
Source: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-15706
Reference (s):
- https://security.netapp.com/advisory/ntap-20200731-0008/
- https://lists.gnu.org/archive/html/grub-devel/2020-07/msg00034.html
- URL: https://lists.gnu.org/archive/html/grub-devel/2020-07/msg00034.html
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200011
- URL: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200011