Yes, I just pointed out the obvious one. There is other work needs doing to proeprly sanitize your inputs.
Basically any user input you use in a query should be cleaned properly - that is, make sure it's been through the vbulletin GPC cleaner, and unless you have specific reasons not to, use escape_string.
And of course NEVER use $_GET, $_POST or $_REQUEST directly. Always run all input through the vbulletin GPC cleaner.
Suggest you read this excellent article:
https://vborg.vbsupport.ru/showthread.php?t=154411
-- hugh