If you wish to allow users to enter a search term and use Perl's internal grep function to search an index file is this script a secure way to do it? By using quotemeta on the user input I can not see how you can hack this, even though the untainting of the user search term is global to allow searching for strings other than pure alphanumberic. I am worried about the interpolation into the grep. Can anyone see security holes? 

#!/usr/bin/perl -wT
use strict;
use CGI;
use Fcntl (':flock');

# clean up the environment for CGI use
BEGIN {
    delete @ENV{qw(IFS CDPATH ENV BASH_ENV)};
    $ENV{'PATH'} = '/bin:/usr/bin:';
}

$CGI::DISABLE_UPLOADS = 1;
$CGI::POST_MAX        = 1024;
my $query             = new CGI;
my $db_file           = 'c:/test.pl';
my $flock             = 1;
my $timeout           = 15;

my $find = $query->param('search');
$find    = quotemeta $find;
$find    = ($find =~ m/^(.+)$/) ? $1 : '';
die_nice("Please specify a search term!") unless $find;

# get the data into an array, retrun a reference to that array
my $data_ref = get_data($db_file);

# do the search
my @lines = grep{ /$find/i }@$data_ref;

# do something with @lines

[download]

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

In reply to Is this CGI search secure? by tachyon

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