Re: What are the top 10 common security risk of a new site? What are the countermeasu
If you use a CMS, do not use 'admin' for the admin account and use a good password. ( at least 2 each of upper, lower, digit, punctuation )
Do not use hacked authoring/FTP tools. Some of those add stuff to your code.
Don't let your little brother near your computer.
Don't trust anything a user inputs. Sanitize anything going into a database and sanitize html entities that you might display on your site.
Use some sort of captcha to prevent spambots.