The initial state of your process's environment is controlled by the parent process, and is thus tainted. 

$ echo '#!/usr/bin
> echo owned
> ' > ~/evil/ls

$ chmod 755 ~/evil/ls

$ PATH=~/evil/:"$PATH" script.pl
owned

[download]

The environment needs to be scrubbed.

In reply to Re: Doubt in perl taint by ikegami
in thread Doubt in perl taint by lakshmananindia

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