PHP remote file inclusion vulnerability in download.php in the Adam van Dongen Forum (com_forum) component (aka phpBB component) 1.2.4RC3 and earlier for Mambo allows remote attackers to execute arbitrary PHP code via a URL in the phpbb_root_path parameter.
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.