Exclude certain packages from upgrading while upgrading everything else in Debian

I use Debian Sid, and this one package, Firefox, has an update with a grave bug found with apt-listbugs. I want to exclude that package from upgrading while upgrading everything else. There is a way to do this, but it is tedious with copy and pasting certain packages to upgrade and leaving some packages out. How can I exclude certain packages from upgrading with a single command?