Hello monks,
Iam trying to create an if statement to distinguish Traversal Atatcks from Null Byte Injection.
Problem is that i cannot seem to telle perl about "%00| at the end of string. it cannot detect it even if i specify it. How can i show perl what is a null char? 
if ( param('select') )
{
    unless (grep { $_ eq param('select') } @display_files)
    {
    if ( param('select') =~ /%/ )
    {
            $passage = "*Null Byte Injection* attempted & logged!";
        print br() x 2, h1( {class=>'big'}, $passage );
    }
    else
        {
            $passage = "*Backwards Directory Traversal* attempted & lo
+gged!";
        print br() x 2, h1( {class=>'big'}, $passage );
    }
    
     $select = $dbh->prepare( "UPDATE guestlog SET passage=?, date=?, 
+counter=counter+1 WHERE host=?" );
    $select->execute( $passage, $date, $host );
    
        exit;
    }
    
    open(FILE, "<../data/text/$passage.txt") or die $!;

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2006-10-11 Retitled by ysth, as per Monastery guidelines
Original title: 'How to specify a Null chat in a match operation'

In reply to How to specify a Null char in a match operation by Nik

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