The vB recently anounced Critical Update is affected by this hack.
Please go to:
http://www.vbulletin.com/forum/showthread.php?t=125480
And download the 3.0.5 init.php file ASAP to plug this vulnerability.
You will need to modify that file in order to run this hack.
In the new init.php, please make the following changes:
Find: (line 792 in a clean file)
PHP Code:
'isbannedgroup' => 32
Replace with:
PHP Code:
'isbannedgroup' => 32,
'ismodifiablegroup' => 64
Find: (line 844 in a clean file)
PHP Code:
'caneditreputation' => 4194304
Replace with:
PHP Code:
'caneditreputation' => 4194304,
'canmodify' => 8388608