An attacker can prepare a local repository in such a way that, when cloned, will execute arbitrary code during the operation.

Git is a revision control system. The Git project recommends to avoid working in untrusted repositories, and instead to clone it first with git clone --no-local to obtain a clean copy. Git has specific protections to make that a safe operation even with an untrusted source repository, but vulnerabilities allow those protections to be bypassed. In the context of cloning local repositories owned by other users, this vulnerability has been covered in CVE-2024-32004. But there are circumstances where the fixes for CVE-2024-32004 are not enough: For example, when obtaining a .zip file containing a full copy of a Git repository, it should not be trusted by default to be safe, as e.g. hooks could be configured to run within the context of that repository. The problem has been patched in versions 2.45.1, 2.44.1, 2.43.4, 2.42.2, 2.41.1, 2.40.2, and 2.39.4. As a workaround, avoid using Git in repositories that have been obtained via archives from untrusted sources.

Git is a revision control system. Prior to versions 2.45.1, 2.44.1, 2.43.4, 2.42.2, 2.41.1, 2.40.2, and 2.39.4, when cloning a local source repository that contains symlinks via the filesystem, Git may create hardlinks to arbitrary user-readable files on the same filesystem as the target repository in the objects/ directory. Cloning a local repository over the filesystem may creating hardlinks to arbitrary user-owned files on the same filesystem in the target Git repository's objects/ directory. When cloning a repository over the filesystem (without explicitly specifying the file:// protocol or --no-local), the optimizations for local cloning will be used, which include attempting to hard link the object files instead of copying them. While the code includes checks against symbolic links in the source repository, which were added during the fix for CVE-2022-39253, these checks can still be raced because the hard link operation ultimately follows symlinks. If the object on the filesystem appears as a file during the check, and then a symlink during the operation, this will allow the adversary to bypass the check and create hardlinks in the destination objects directory to arbitrary, user-readable files. The problem has been patched in versions 2.45.1, 2.44.1, 2.43.4, 2.42.2, 2.41.1, 2.40.2, and 2.39.4.

Cloning local Git repository by untrusted user allows the untrusted user to modify objects in the cloned repository at will