Imagine you plan to offer an application service hosted on a common LINUX box. That is not very difficult at all, so you have to go on and choose your favourite distribution, installing and configuring some servers (e.g. web- and database servers) and finally adding your web based application itself. Sooner or later the project was announced, you'll have to face with security issues, depending hardly on the fact, that Internet web applications are always a good target for possible offences. Right now you are in the circuit of fixing bugs, upgrading software and closing open doors.