$re = '/<(?<fieldname>[^>]+)>(?<fieldvalue>[^<]*)<\/\1>/m';
$str = '<Vuln>
<CrawlTraffic>UE9TVCAvcnUvY29udHJhY3RvcnMvdGVuZGVycy9yZXF1ZXN0LyBIVFRQLzEuMQ0KQWNjZXB0OiB0ZXh0L2h0bWwsYXBwbGljYXRpb24veGh0bWwreG1sLGFwc=</CrawlTraffic>
</Vuln>';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php