Possible to update-ref remote repository?

Hello -

Wondering if it's possible to do the equivalent of the update-ref command remotely. Or I guess another way of putting it would be to git-push to a remote repository without needing a local clone of the repo.

Trying do something like:

git push <remote-repo-url>  <sha1>:refs/heads/mybranchtoupdate

where I know that <sha1> already exists on the remote. I'd like to avoid the need to clone a local copy of the repo. Wondering if there might be some plumbing command(s) that could accomplish this?

Regards, Jesse

P.S. I think think a minimal way to do this using git push would be:

git init git remote add origin <remote-repo-url> git fetch origin <sha1>:refs/heads/mybranchtoupdate git push origin refs/heads/mybranchtoupdate:refs/heads/mybranchtoupdate

Seems that if it's known that <sha1> already exists on the remote, the fetch is unnecessary network overhead?