there is since 02 march 2021 many updates Securities patches
see also impact reported on Shim ( size keys hash) , fwupd , SBAT https://www.debian.org/security/2021-GRUB-UEFI-SecureBoot/index
Thanks for the pointer. We aren’t affected because we don’t support (in)secure boot (don’t want to rely on M$), but updating it is a good idea anyway.
there is many patches on git savannah , i dont think it will only concerns part Secureboot , but you have also to think for users with dual boot with windows , and Grub are extended to others platforms ( aarch64, risc-v , etc )