why is this language so insecure?

[tiger86]

I don't know much about php but I do know how insecure it is and it is driving me up the wall. Why is this language insecure and what can I do to make php scripts more secure?

[R0bb0b]

Declare all of your variables and assign them a value innitially.
use constants if used on included files and such.
validate all user input, leave no open doors.
For one example, I often times use arrays for known input content and say if(in_array(blah blah)){//do somthing}else{ exit(); }, I've got dozens of them.

exit() shuts down the entire script and it stops processing at that point. Just things like that, think like a hacker and how you would try to header/sql inject.

But these concepts are for all web languages though.

[pritaeas]

type:

php defensive programming

in Google and look for the two links from php-classes.org. They'll show you some things about how to address these problems.