There is no exploit involved. Though, there is a bug involved. The described issue generates an error screen using the links provided; however, this is only because there is a bug with single character search strings. Using anything longer than the string mentioned in the initial report (1 letter in length) will not generate an error message, and will not allow any sql injection. There is no exploit, this is an invalid entry. The bug involved can be seen here: http://www.vbulletin.com/forum/project.php?issueid=25377
