As reported by ZZRabbit in the forums and confirmed by others, and restated on our blog, there is a serious issue with v17.0. A reboot after installing the new (security) kernel, you will get a kernel panic.
Note: This only affects v17.0.
To fix the issue:
apt install --reinstall -y initramfs-tools
dpkg-reconfigure linux-image-5.10.0-14-amd64
Note that this bug is the symptom of #1735.