Comment by Tuna-Fish
5 days ago
A symlink is just a special file that contains a string of text, it's not tightly bound to the target like a hard link. You can write anything into that string of text, including, say, "~/.bashrc". Then you can ship that symlink onto another system, and it suddenly points to your .bashrc.
Git just moves symlinks across systems as is, so yes, you can use git to deploy the exploit.
As pedantry, to the very best of my knowledge symlinks could not contain "~" and have it mean $HOME - that's a shell-ism (or os.path.expanduser equivalent in your library). I was suspecting the attack vector may have used "/home/runner" or "/home/ubuntu" as very common paths that could exist and be writable by the user