Use Text::xSV:

  use Text::xSV;
  
  my $csv = Text::xSV->new(
    filename => "foo.csv",
    header   => \@column_names,
  );
  while ($csv->get_row()) {
  # You could use fetchrow_hash here, but I'll just print a message
  # If you want a HoH or AoH, read up on extract_hash
  my ($name, $alert_publisher) = $csv->extract(qw(Name alert_publisher
+));
  print "Dll: $name\t is " 
        . (($alert_publisher eq 'X')? '' : 'not ')
        . "an alert publisher\n";
  }
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It's worth noting that your problem as posed overwrites the hash each time you read in a new line. If this is not what you want, you need to construct an array (or a hash) of hashes ... see the comment for pointers.