Form the tiny snippet you put i can oly guess that the value for $username comes from outside the script and you are not untainting it before passing it to the shell. As for the error showing up without the -T, IIRC perl automaticlly turns on taint mode when the script is suid. DO a search on perlsec for more info

In reply to Re: Insecure Dependency Message by Desdinova
in thread Insecure Dependency Message by wheakory

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