What kind of danger specifically do you have in mind? This is a very different question if it's about supposed security exploits vs. losing work by overwriting your working copy.

Both.

The most common worry is to lose my working copy and having a hard time recovering it (git-reflog(1) usually helps recover those).

However, I'm also worried about a git server being hacked and me pulling from it and blindly incorporating those changes as if they were fine.

I have a git server where I push my working copy often for backup, or for continuing work in a different computer. I usually rebase the changes often after downloading a working branch.

I always sign all of my commits with PGP, so that I can check the integrity of the commits. So I usually git-fetch(1), check the integrity of the signatures with git-log(1), and then rebase as appropriate.

If I do a git-pull(1), especially a rebase one, I'll have a hard time knowing what I pulled, and so it's a bit harder to verify.

The question seems answerable if you assume that the OP is asking for any danger.