At this site, the following was written on March 25, 2006:

I have been reading up on web security and I am getting paranoid.
I operate under taint mode - although I must confess to being a little
in the dark as to what that means.
I am using the following code in order to filter input from a form.

CODE
$TEST =~ s/[^a-zA-Z0-9@\/.,: ]//g;

It works as expected but I am trying to make it as secure as possible 
+and
found that if a user enters '<SCRIPT>' into a form field it treats it 
+as a
Java Code and it is not filtered. I assume that I could follow this wi
+th some
other code and do some harm. I need to avoid this security hole and ob
+viously
I could check for the word '<SCRIPT>' in STDIN.
Is there a better way of doing this and what other holes should I be a
+ware of?

Keith
[download]

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