The Simple Download Counter plugin for WordPress is vulnerable to Arbitrary File Read in all versions up to, and including, 2.0 via the 'simple_download_counter_download_handler'. This makes it possible for authenticated attackers, with Author-level access and above, to extract sensitive data including any local file on the server, such as wp-config.php or /etc/passwd.
The product allows user input to control or influence paths or file names that are used in filesystem operations.