On Windows, if Git LFS operates on a malicious repository with a `..exe` file as well as a file named `git.exe`, and `git.exe` is not found in `PATH`, the `..exe` program will be executed, permitting the attacker to execute arbitrary code. This does not affect Unix systems. The vulnerability occurs because when Git LFS detects that the program it intends to run does not exist in any directory listed in `PATH`, then Git LFS passes an empty string as the executable file path to the Go `os/exec` package, which contains a bug such that, on Windows, it prepends the name of the current working directory (i.e., `.`) to the empty string without adding a path separator, and as a result searches in that directory for a file with the base name `.` combined with any file extension from `PATHEXT`, executing the first one it finds.