ATutor 1.4.1 through 1.5.1-pl1 allows remote attackers to execute arbitrary PHP functions via a direct request to forum.inc.php with a modified addslashes parameter with either the (1) asc or (2) desc parameters set, possibly due to an eval injection vulnerability.
http://www.vupen.com/english/advisories/2005/2228
http://securitytracker.com/id?1015165