Code execution via unguarded Repo.init template option

Code execution in GitPython before 3.1.58 allows attackers to run arbitrary code via a crafted template path passed to Repo.init. Repo.init forwards keyword arguments directly to git init without an unsafe-option guard, letting template reference an attacker-controlled directory whose hooks are copied into the new repository. Exposure requires an application to let an attacker influence that argument and reach a staged hook directory; the planted hook then runs with the host process's privileges on the next Git operation in that repository.