The Download Manager plugin for WordPress is vulnerable to Directory Traversal in all versions up to, and including, 3.3.08 via the 'wpdm_newfile' action. This makes it possible for authenticated attackers, with Author-level access and above, to overwrite select file types outside of the originally intended directory, which may cause a denial of service.
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.