Git is an open source, scalable, distributed revision control system. Versions prior to 2.30.6, 2.31.5, 2.32.4, 2.33.5, 2.34.5, 2.35.5, 2.36.3, and 2.37.4 are subject to exposure of sensitive information to a malicious actor. When performing a local clone (where the source and target of the clone are on the same volume), Git copies the contents of the source's $GIT_DIR/objects directory into the destination by either creating hardlinks to the source contents, or copying them (if hardlinks are disabled via --no-hardlinks).

A malicious actor could convince a victim to clone a repository with a symbolic link pointing at sensitive information on the victim's machine. This can be done either by having the victim clone a malicious repository on the same machine, or having them clone a malicious repository embedded as a bare repository via a submodule from any source, provided they clone with the --recurse-submodules option. Git does not create symbolic links in the $GIT_DIR/objects directory.

The problem has been patched in the versions published on 2022-10-18, and backported to v2.30.x. Potential workarounds: Avoid cloning untrusted repositories using the --local optimization when on a shared machine, either by passing the --no-local option to git clone or cloning from a URL that uses the file:// scheme. Alternatively, avoid cloning repositories from untrusted sources with --recurse-submodules or run git config --global protocol.file.allow user.