Single ticks are insufficient, passing to the shell at all is trouble. merlyn has a post (feeding text to a process, and capturing its output, safely) which shows a safe way to `echo $INPUT | Some Command` (if the OP insists on pursuing this approach).

Good Day,
    Dean

In reply to Re^2: change unix password with cgi-script by duelafn
in thread change unix password with cgi-script by miggel15

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