Hello Monks!
This has been done before but I am trying to write my own CGI/Traceroute program so I can become enlightened.

The below code works but it is not secure- someone can type 127.0.0.1 | cat /etc/passwd and grab my password file!
Ack!
If I uncomment the line below the code doesn't work:
$value =~ s /|/ /g;
Any ideas on what I need to do so the code is totally secure and works?
Thanks!! 
#!/usr/bin/perl -w

use CGI;

my $query = new CGI;

$value = $query->param('trace');

#$value =~ s (/;#!"'`|)/ /g;
$value =~ s /;/ /g;
$value =~ s /#/ /g;
$value =~ s /!/ /g;
$value =~ s /"/ /g;
$value =~ s /'/ /g;
$value =~ s /`/ /g;
#$value =~ s /|/ /g;

open (TRACE, "traceroute $value |");
@traceroute = <TRACE>;
close (TRACE);

print "Content-Type: text/html\n\n";

print "<html>\n<head>\n<title>\nRavenGate TraceRoute Results\n</title>
+\n</head>\n<body>\n";

print "Hello There- I am writing this from scratch so please be patien
+t.  Thanks!\n\n";


foreach $item (@traceroute) {
print "<BR>$item\n\n";
}

print "</body>\n</html>\n";

exit (0);

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In reply to CGI and Traceroute by Anonymous Monk

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