SQL injection is one of type of web hacking that require any web based application which
is connected to a back-end database, and it might just work even if the admin is patchhappy.
It attacks on the web application (like ASP, JSP, PHP, CGI, etc) itself rather than on
the web server or services running in the OS.
What is SQL Injection?
It is a trick to inject SQL query/command as an input possibly via webpages. Many web
pages take parameters from web user, and make SQL query to the database. Take for
instance when a user login, web page that user name and password and make SQL query
to the database to check if a user has valid name and password. With SQL Injection, it is
possible for us to send crafted user name and/or password field that will change the SQL
query and thus grant us something else.