DBD::File versions before 1.651 for Perl do not ensure the table file is not a symlink to an untrusted location. The completetablename method builds the absolute table file path without checking whether the file is a symbolic link. A link inside the data directory can point to a table file at any path outside of the configured fdir and fdir_search directories. Callers of file-based drivers can read or write files outside of the data directory.