go-git is an extensible git implementation library written in pure Go. Prior to 5.19.2 and 6.0.0-alpha.5, worktree operations (including checkout, status, and add) resolve symbolic links inside the working tree without confining resolution to the worktree boundary, so a maliciously crafted repository containing a symlink can cause go-git to read from or write to files outside the intended working directory when the repository is cloned and its worktree operations are used. Versions 5.19.2 and 6.0.0-alpha.5.
The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.