I think its very clear... I decided to try it as the author stated above. I used echo because well - I like my system the way it is. And its a good thing I did too because the command executed. This is what I have: 
#!/usr/bin/perl

$a ="${system(\"echo 'hello from system'\")}\n";

print "$a";

[download]
And this is the output: 
hello from system
stupid.pl

[download]

I think this is what the author is talking about. Now when I use the q or qq it responds as you said so I guess that perl treats qq differently than an actual double quote. Something I didn't know. Interestingly enough it prints the name of the script out as well when this command executes... not sure why.

In reply to Re: Re: Trojan Horse? (taint mode) by cfreak
in thread Trojan Horse? (taint mode) by IraTarball

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