Git is a fast, scalable, distributed revision control system with an unusually rich command set that provides both high-level operations and full access to internals. When reading a config value, Git strips any trailing carriage return and line feed (CRLF). When writing a config entry, values with a trailing CR are not quoted, causing the CR to be lost when the config is later read. When initializing a submodule, if the submodule path contains a trailing CR, the altered path is read resulting in the submodule being checked out to an incorrect location. If a symlink exists that points the altered path to the submodule hooks directory, and the submodule contains an executable post-checkout hook, the script may be unintentionally executed after checkout. This vulnerability is fixed in v2.43.7, v2.44.4, v2.45.4, v2.46.4, v2.47.3, v2.48.2, v2.49.1, and v2.50.1.
Git GUI is a convenient graphical tool that comes with Git for Windows. Its target audience is users who are uncomfortable with using Git on the command-line. Git GUI has a function to clone repositories. Immediately after the local clone is available, Git GUI will automatically post-process it, among other things running a spell checker called `aspell.exe` if it was found. Git GUI is implemented as a Tcl/Tk script. Due to the unfortunate design of Tcl on Windows, the search path when looking for an executable _always includes the current directory_. Therefore, malicious repositories can ship with an `aspell.exe` in their top-level directory which is executed by Git GUI without giving the user a chance to inspect it first, i.e. running untrusted code. This issue has been addressed in version 2.39.1. Users are advised to upgrade. Users unable to upgrade should avoid using Git GUI for cloning. If that is not a viable option, at least avoid cloning from untrusted sources.