//-- MyBB 1.10 New CrossSiteScripting ' member.php ' --//

Webattack :-
/mybb/member.php?action=do_login&username=[usrname]&password=[pass]&url="><script>alert(1);</script>

//-- FixIT --//

Open member.php
GoTo Line :- 1030 ..


if($mybb->input['url'])
{
redirect($mybb->input['url'], $lang->redirect_loggedin);
}


Replace It With

if($mybb->input['url'])
{
redirect(htmlspecialchars($mybb->input['url']), $lang->redirect_loggedin);
}
//-- --//