Earlier I got some thinking about how PHP WORM can inject the client computer, and it's like this:
1. WORM_MAKER has infect the site with worm script, where in that page is checks the OS that the client using.
2. Like example if user have used WINDOWS OS, then the script will generate the worm code for WINDOWS OS.
3. Then that page will make that code downloaded silently.
It's possible to do?
Absolutely in PHP code?