member2.php in vBulletin 2.2.9 and earlier does not properly restrict the $perpage variable to be an integer, which causes an error message to be reflected back to the user without quoting, which facilitates cross-site scripting (XSS) and possibly other attacks.
SQL injection vulnerability in calendar.php for vBulletin Forum 2.3.x before 2.3.4 allows remote attackers to steal sensitive information via the eventid parameter.