My palms got a little sweaty as I read the replies to the node concerning security risks with Matt's Scripts. I have never used those, but it got me wondering about my own use of sendmail. I have been using the examples from the Mouse book CGI Programming with Perl (even after all their dire warnings about using it at) with decent results (people are getting the e-mails!). I'm still trying to get my head around the security issues and want some XP'ed monks to take a look and tell me if I'm overlooking anything. The Validate.pm (doing the untainting) is on my scratchpad (thanks to chromatic for his help on this module and calling it).

So, 1) Is this secure? 2) Why is it when I add -T to the shebang, I get a Can't locate Validate.pm in @INC error (works fine without it)? 
#!/usr/bin/perl 

print "Content-type: text/plain\n\n";

use strict;
use warnings;
use Validate;
use CGI qw(:standard);

my @errors;

my $sendto     = Validate->alphanum (param('sendto'));
push @errors, "Missing or invalid addressee\n" unless $sendto;

my $email    = Validate->email (param('email'));
push @errors, "Missing or invalid e-mail address\n" unless $email;

# similar untainting for all other user input here, then...

if (@errors) { &printerrors; exit; }
    
#-----------send email ---------

    $sendto .= "\@somewebsite.org";

    open(MAIL,"| /usr/lib/sendmail -t") or die "Could not open sendmai
+l: $!";
        print MAIL "From: $name\n";
        print MAIL "To: $sendto\n";
        print MAIL "Subject: $subject\n\n";
        print MAIL "E-mail: $email\n\n";
        print MAIL "Message: $message\n\n";
        print MAIL "\n\n";
    close MAIL or die "Could not close sendmail: $!";

print "Thanks for your message.";    
exit;

sub printerrors {
    for (@errors) { print $_."\n" }
}

__END__

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Thank you all!

—Brad
"A little yeast leavens the whole dough."

In reply to Security of Sendmail and -T error by bradcathey

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