upload-labs通关手册

最近在练习文件上传，所以记录一下自己练习的过程，既能帮助自己以后复习，同时也能帮到初学者。主要用到的工具是Burpsuite。首先我们应该明白上传文件的目的是什么，通过上传文件将web后门上传并被成功解析。

Pass-01

首先查看源码在这里插入图片描述通过源码可以看到，第一关是在本地前段进行验证，使用的是前端JS脚本，所以呢，你让它不起作用不就完了，前端我们是可以修改的，在前端JS函数中加上.php文件，然后上传PHP文件。（具体怎么修改，直接查看源代码，然后修改，然后保存本地，再然后点击访问，然后上传即可）

Pass-02

源码：在这里插入图片描述这个其实也很简单，我们发现它只判断content-type，那所以只要burpsuite抓包修改content-type的类型就可以成功绕过，然后上传。上传成功如图：

Pass-03

步骤一样，第一步先查看源码在这里插入图片描述通过源代码分析，我们能够看出来是黑名单过滤，这里有很多绕过方式，抓包修改后缀为php5、php3、phtml、pht等可解析的文件后缀即可

Pass-04

查看源码：

$is_upload = false;
$msg = null;
if (isset($_POST['submit'])) {
    if (file_exists(UPLOAD_PATH)) {
        $deny_ext = array(".php",".php5",".php4",".php3",".php2","php1",".html",".htm",".phtml",".pht",".pHp",".pHp5",".pHp4",".pHp3",".pHp2","pHp1",".Html",".Htm",".pHtml",".jsp",".jspa",".jspx",".jsw",".jsv",".jspf",".jtml",".jSp",".jSpx",".jSpa",".jSw",".jSv",".jSpf",".jHtml",".asp",".aspx",".asa",".asax",".ascx",".ashx",".asmx",".cer",".aSp",".aSpx",".aSa",".aSax",".aScx",".aShx",".aSmx",".cEr",".sWf",".swf");
        $file_name = trim($_FILES['upload_file']['name']);
        $file_name = deldot($file_name);//删除文件名末尾的点
        $file_ext = strrchr($file_name, '.');
        $file_ext = strtolower($file_ext); //转换为小写
        $file_ext = str_ireplace('::$DATA', '', $file_ext);//去除字符串::$DATA
        $file_ext = trim($file_ext); //收尾去空

        if (!in_array($file_ext, $deny_ext)) {
            $temp_file = $_FILES['upload_file']['tmp_name'];
            $img_path = UPLOAD_PATH.'/'.date("YmdHis").rand(1000,9999).$file_ext;
            if (move_uploaded_file($temp_file, $img_path)) {
                $is_upload = true;
            } else {
                $msg = '上传出错！';
            }
        } else {
            $msg = '此文件不允许上传!';
        }
    } else {
        $msg = UPLOAD_PATH . '文件夹不存在,请手工创建！';
    }
}

还是黑名单过滤，几乎过滤了所有后缀名，但是没有过滤.htaccess，所有先上传一个后缀名为.htaccess文件，里面写上SetHandler application/x-httpd-php，之后所有的文件都会以PHP文件进行解析，那就正常上传图片，然后访问即可

此处用到知识点：

.htaccess文件 -服务通过.htaccess文件修改解析规则条件：必须为apache搭建平台

Pass-05

这一关和上一关几乎一模一样，但是没有进行大小写过滤，所以，大小写修改后缀名，然后成功上传。在这里插入图片描述上传结果如图：

Pass-06

源码：

$is_upload = false;
$msg = null;
if (isset($_POST['submit'])) {
    if (file_exists(UPLOAD_PATH)) {
        $deny_ext = array(".php",".php5",".php4",".php3",".php2",".html",".htm",".phtml",".pht",".pHp",".pHp5",".pHp4",".pHp3",".pHp2",".Html",".Htm",".pHtml",".jsp",".jspa",".jspx",".jsw",".jsv",".jspf",".jtml",".jSp",".jSpx",".jSpa",".jSw",".jSv",".jSpf",".jHtml",".asp",".aspx",".asa",".asax",".ascx",".ashx",".asmx",".cer",".aSp",".aSpx",".aSa",".aSax",".aScx",".aShx",".aSmx",".cEr",".sWf",".swf",".htaccess");
        $file_name = $_FILES['upload_file']['name'];
        $file_name = deldot($file_name);//删除文件名末尾的点
        $file_ext = strrchr($file_name, '.');
        $file_ext = strtolower($file_ext); //转换为小写
        $file_ext = str_ireplace('::$DATA', '', $file_ext);//去除字符串::$DATA
        
        if (!in_array($file_ext, $deny_ext)) {
            $temp_file = $_FILES['upload_file']['tmp_name'];
            $img_path = UPLOAD_PATH.'/'.date("YmdHis").rand(1000,9999).$file_ext;
            if (move_uploaded_file($temp_file,$img_path)) {
                $is_upload = true;
            } else {
                $msg = '上传出错！';
            }
        } else {
            $msg = '此文件不允许上传';
        }
    } else {
        $msg = UPLOAD_PATH . '文件夹不存在,请手工创建！';
    }
}

仍然是过滤了很多后缀名，这个时候我们可以在后面加后缀名后面加空格进行绕过在这里插入图片描述结果如图所示：成功上传！

Pass-07

源码：

$is_upload = false;
$msg = null;
if (isset($_POST['submit'])) {
    if (file_exists(UPLOAD_PATH)) {
        $deny_ext = array(".php",".php5",".php4",".php3",".php2",".html",".htm",".phtml",".pht",".pHp",".pHp5",".pHp4",".pHp3",".pHp2",".Html",".Htm",".pHtml",".jsp",".jspa",".jspx",".jsw",".jsv",".jspf",".jtml",".jSp",".jSpx",".jSpa",".jSw",".jSv",".jSpf",".jHtml",".asp",".aspx",".asa",".asax",".ascx",".ashx",".asmx",".cer",".aSp",".aSpx",".aSa",".aSax",".aScx",".aShx",".aSmx",".cEr",".sWf",".swf",".htaccess");
        $file_name = trim($_FILES['upload_file']['name']);
        $file_ext = strrchr($file_name, '.');
        $file_ext = strtolower($file_ext); //转换为小写
        $file_ext = str_ireplace('::$DATA', '', $file_ext);//去除字符串::$DATA
        $file_ext = trim($file_ext); //首尾去空
        
        if (!in_array($file_ext, $deny_ext)) {
            $temp_file = $_FILES['upload_file']['tmp_name'];
            $img_path = UPLOAD_PATH.'/'.$file_name;
            if (move_uploaded_file($temp_file, $img_path)) {
                $is_upload = true;
            } else {
                $msg = '上传出错！';
            }
        } else {
            $msg = '此文件类型不允许上传！';
        }
    } else {
        $msg = UPLOAD_PATH . '文件夹不存在,请手工创建！';
    }
}

第7关我们发现多了一个函数，就是首位去空，发现加空格以不再有效。那就没有别的了吗？当然不是了，出了空格还有很多可以加，它虽然过滤了空格，但是没有过滤“.”！所以，我们可以在后缀名后面加“.”即可绕过上传，正所谓，条条大路通罗马，这里我们也可以看出来，黑名单的弊端！在这里插入图片描述成功

Pass-08

源码

$is_upload = false;
$msg = null;
if (isset($_POST['submit'])) {
    if (file_exists(UPLOAD_PATH)) {
        $deny_ext = array(".php",".php5",".php4",".php3",".php2",".html",".htm",".phtml",".pht",".pHp",".pHp5",".pHp4",".pHp3",".pHp2",".Html",".Htm",".pHtml",".jsp",".jspa",".jspx",".jsw",".jsv",".jspf",".jtml",".jSp",".jSpx",".jSpa",".jSw",".jSv",".jSpf",".jHtml",".asp",".aspx",".asa",".asax",".ascx",".ashx",".asmx",".cer",".aSp",".aSpx",".aSa",".aSax",".aScx",".aShx",".aSmx",".cEr",".sWf",".swf",".htaccess");
        $file_name = trim($_FILES['upload_file']['name']);
        $file_name = deldot($file_name);//删除文件名末尾的点
        $file_ext = strrchr($file_name, '.');
        $file_ext = strtolower($file_ext); //转换为小写
        $file_ext = trim($file_ext); //首尾去空
        
        if (!in_array($file_ext, $deny_ext)) {
            $temp_file = $_FILES['upload_file']['tmp_name'];
            $img_path = UPLOAD_PATH.'/'.date("YmdHis").rand(1000,9999).$file_ext;
            if (move_uploaded_file($temp_file, $img_path)) {
                $is_upload = true;
            } else {
                $msg = '上传出错！';
            }
        } else {
            $msg = '此文件类型不允许上传！';
        }
    } else {
        $msg = UPLOAD_PATH . '文件夹不存在,请手工创建！';
    }
}

这里我们发现，大小写不行，加点不行，加空格也不行，但是没有对::$DATA进行过滤,所以在后缀名中加::$DATA进行绕过知识点：文件名+$DATA - 服务必须是windows, 必须是php, php在window的时候如果文件名+"$DATA"会把::$DATA之后的数据当成文件流处理,不会检测后缀名.且保持"::$DATA"之前的文件名他的目的就是不检查后缀名.... 在这里插入图片描述成功

Pass-09

源码：

$is_upload = false;
$msg = null;
if (isset($_POST['submit'])) {
    if (file_exists(UPLOAD_PATH)) {
        $deny_ext = array(".php",".php5",".php4",".php3",".php2",".html",".htm",".phtml",".pht",".pHp",".pHp5",".pHp4",".pHp3",".pHp2",".Html",".Htm",".pHtml",".jsp",".jspa",".jspx",".jsw",".jsv",".jspf",".jtml",".jSp",".jSpx",".jSpa",".jSw",".jSv",".jSpf",".jHtml",".asp",".aspx",".asa",".asax",".ascx",".ashx",".asmx",".cer",".aSp",".aSpx",".aSa",".aSax",".aScx",".aShx",".aSmx",".cEr",".sWf",".swf",".htaccess");
        $file_name = trim($_FILES['upload_file']['name']);
        $file_name = deldot($file_name);//删除文件名末尾的点
        $file_ext = strrchr($file_name, '.');
        $file_ext = strtolower($file_ext); //转换为小写
        $file_ext = str_ireplace('::$DATA', '', $file_ext);//去除字符串::$DATA
        $file_ext = trim($file_ext); //首尾去空
        
        if (!in_array($file_ext, $deny_ext)) {
            $temp_file = $_FILES['upload_file']['tmp_name'];
            $img_path = UPLOAD_PATH.'/'.$file_name;
            if (move_uploaded_file($temp_file, $img_path)) {
                $is_upload = true;
            } else {
                $msg = '上传出错！';
            }
        } else {
            $msg = '此文件类型不允许上传！';
        }
    } else {
        $msg = UPLOAD_PATH . '文件夹不存在,请手工创建！';
    }
}

这里，在后缀后加上点+空格+点即可成功绕过，在这里插入图片描述

pass-10

这里的步骤和之前的一样，重复的我就不再写了，浪费时间，还是先看源码，这是第一步，通过源码去分析它是黑名单过滤还是白名单，然后看它漏掉了哪项。第10关采用双写绕过，后缀名为 .phphpp 即可成功上传，结果一样，我就不再一一截图了。

Pass-11

查看源码，我们发现11关是白名单判断，因此可以采用%00截断绕过在这里插入图片描述

但是有环境限制： php版本要小于5.3.4，5.3.4及以上

magic_quotes_gpc需要为OFF状态

如果你在做实验时发现一直上传错误，请看你是否满足我上面说的两个环境限制，如果不满足就会上传错误，如果已经设置好，则可以正常上传，得到正确结果。在这里插入图片描述

Pass-12

这一关和11关一样，只是这个是POST提交，上面那个是GET提交，用的方法是一样的！这里就不再过多阐述

Pass-13

源码：

function getReailFileType($filename){
    $file = fopen($filename, "rb");
    $bin = fread($file, 2); //只读2字节
    fclose($file);
    $strInfo = @unpack("C2chars", $bin);    
    $typeCode = intval($strInfo['chars1'].$strInfo['chars2']);    
    $fileType = '';    
    switch($typeCode){      
        case 255216:            
            $fileType = 'jpg';
            break;
        case 13780:            
            $fileType = 'png';
            break;        
        case 7173:            
            $fileType = 'gif';
            break;
        default:            
            $fileType = 'unknown';
        }    
        return $fileType;
}

$is_upload = false;
$msg = null;
if(isset($_POST['submit'])){
    $temp_file = $_FILES['upload_file']['tmp_name'];
    $file_type = getReailFileType($temp_file);

    if($file_type == 'unknown'){
        $msg = "文件未知，上传失败！";
    }else{
        $img_path = UPLOAD_PATH."/".rand(10, 99).date("YmdHis").".".$file_type;
        if(move_uploaded_file($temp_file,$img_path)){
            $is_upload = true;
        } else {
            $msg = "上传出错！";
        }
    }
}

13关往后与之前不一样，13关之后的是上传图片马。这里我们看到，它只判断前两个字节，所以自己搞一个图片，然后编辑，将一句话木马写进去，然后上传即可，访问即可得到。在这里插入图片描述图片上面是乱码，但下面就是被php解析的函数。

Pass-14

跟13关一样。 getimagesize判断图片内置函数可以参考官方文档http://php.net/manual/zh/function.getimagesize.php

Pass-15

这关需要开启php_exif模块，通过php_exif来判断函数类型，具体可以看官方文档http://php.net/manual/zh/function.exif-imagetype.php，接下来还是上传图片马

Pass-16

源码我就不贴了，占地，自己在自己的靶场可以看到。本关综合判断了后缀名、content-type，以及利用imagecreatefromgif判断是否为gif图片，最后对图片再做了一次二次渲染重新创建，所以在上传图片马的时候将上传后的图片马下载下来进行查看，看看它经过而渲染后的图片中的那些数据没有改变，可以通过16进制编辑器查看，然后我们在这些没有变的地方插入一句话，这样就可以成功上传了。之后的操作与之前的关卡一样

Pass-17

本关考察的是条件竞争通过白名单检测后缀名，符合就rename改名，不符合就unlink删除文件可以用burp来发包不断访问，先写一个php写入文件的1.php然后在不断访问这文件就可以看到我们上传的东西了，而且在访问这文件就可以生成另外一个shell了（通过马生成的）在这里插入图片描述

Pass-18

//index.php
$is_upload = false;
$msg = null;
if (isset($_POST['submit']))
{
    require_once("./myupload.php");
    $imgFileName =time();
    $u = new MyUpload($_FILES['upload_file']['name'], $_FILES['upload_file']['tmp_name'], $_FILES['upload_file']['size'],$imgFileName);
    $status_code = $u->upload(UPLOAD_PATH);
    switch ($status_code) {
        case 1:
            $is_upload = true;
            $img_path = $u->cls_upload_dir . $u->cls_file_rename_to;
            break;
        case 2:
            $msg = '文件已经被上传，但没有重命名。';
            break; 
        case -1:
            $msg = '这个文件不能上传到服务器的临时文件存储目录。';
            break; 
        case -2:
            $msg = '上传失败，上传目录不可写。';
            break; 
        case -3:
            $msg = '上传失败，无法上传该类型文件。';
            break; 
        case -4:
            $msg = '上传失败，上传的文件过大。';
            break; 
        case -5:
            $msg = '上传失败，服务器已经存在相同名称文件。';
            break; 
        case -6:
            $msg = '文件无法上传，文件不能复制到目标目录。';
            break;      
        default:
            $msg = '未知错误！';
            break;
    }
}

//myupload.php
class MyUpload{
......
......
...... 
  var $cls_arr_ext_accepted = array(
      ".doc", ".xls", ".txt", ".pdf", ".gif", ".jpg", ".zip", ".rar", ".7z",".ppt",
      ".html", ".xml", ".tiff", ".jpeg", ".png" );

......
......
......  
  /** upload()
   **
   ** Method to upload the file.
   ** This is the only method to call outside the class.
   ** @para String name of directory we upload to
   ** @returns void
  **/
  function upload( $dir ){
    
    $ret = $this->isUploadedFile();
    
    if( $ret != 1 ){
      return $this->resultUpload( $ret );
    }

    $ret = $this->setDir( $dir );
    if( $ret != 1 ){
      return $this->resultUpload( $ret );
    }

    $ret = $this->checkExtension();
    if( $ret != 1 ){
      return $this->resultUpload( $ret );
    }

    $ret = $this->checkSize();
    if( $ret != 1 ){
      return $this->resultUpload( $ret );    
    }
    
    // if flag to check if the file exists is set to 1
    
    if( $this->cls_file_exists == 1 ){
      
      $ret = $this->checkFileExists();
      if( $ret != 1 ){
        return $this->resultUpload( $ret );    
      }
    }

    // if we are here, we are ready to move the file to destination

    $ret = $this->move();
    if( $ret != 1 ){
      return $this->resultUpload( $ret );    
    }

    // check if we need to rename the file

    if( $this->cls_rename_file == 1 ){
      $ret = $this->renameFile();
      if( $ret != 1 ){
        return $this->resultUpload( $ret );    
      }
    }
    
    // if we are here, everything worked as planned :)

    return $this->resultUpload( "SUCCESS" );
  
  }
......
......
...... 
};

和上一关几乎一模一样

Pass-19

$is_upload = false;
$msg = null;
if (isset($_POST['submit'])) {
    if (file_exists(UPLOAD_PATH)) {
        $deny_ext = array("php","php5","php4","php3","php2","html","htm","phtml","pht","jsp","jspa","jspx","jsw","jsv","jspf","jtml","asp","aspx","asa","asax","ascx","ashx","asmx","cer","swf","htaccess");

        $file_name = $_POST['save_name'];
        $file_ext = pathinfo($file_name,PATHINFO_EXTENSION);

        if(!in_array($file_ext,$deny_ext)) {
            $temp_file = $_FILES['upload_file']['tmp_name'];
            $img_path = UPLOAD_PATH . '/' .$file_name;
            if (move_uploaded_file($temp_file, $img_path)) { 
                $is_upload = true;
            }else{
                $msg = '上传出错！';
            }
        }else{
            $msg = '禁止保存为该类型文件！';
        }

    } else {
        $msg = UPLOAD_PATH . '文件夹不存在,请手工创建！';
    }
}

本关考察CVE-2015-2348 move_uploaded_file() 00截断，上传webshell，同时自定义保存名称，直接保存为php是不行的,查看源码发现move_uploaded_file()函数中的img_path是由post参数save_name控制的，因此可以在save_name利用00截断绕过

Pass-20

$is_upload = false;
$msg = null;
if(!empty($_FILES['upload_file'])){
    //检查MIME
    $allow_type = array('image/jpeg','image/png','image/gif');
    if(!in_array($_FILES['upload_file']['type'],$allow_type)){
        $msg = "禁止上传该类型文件!";
    }else{
        //检查文件名
        $file = empty($_POST['save_name']) ? $_FILES['upload_file']['name'] : $_POST['save_name'];
        if (!is_array($file)) {
            $file = explode('.', strtolower($file));
        }

        $ext = end($file);
        $allow_suffix = array('jpg','png','gif');
        if (!in_array($ext, $allow_suffix)) {
            $msg = "禁止上传该后缀文件!";
        }else{
            $file_name = reset($file) . '.' . $file[count($file) - 1];
            $temp_file = $_FILES['upload_file']['tmp_name'];
            $img_path = UPLOAD_PATH . '/' .$file_name;
            if (move_uploaded_file($temp_file, $img_path)) {
                $msg = "文件上传成功！";
                $is_upload = true;
            } else {
                $msg = "文件上传失败！";
            }
        }
    }
}else{
    $msg = "请选择要上传的文件！";
}

通过查看源码可以发现：

$file_name经过reset($file) . '.' . $file[count($file) - 1];处理。

如果上传的是数组的话，会跳过$file = explode('.', strtolower($file));。

并且后缀有白名单过滤：

$ext = end($file); $allow_suffix = array('jpg','png','gif');

而最终的文件名后缀取的是$file[count($file) - 1]，因此我们可以让$file为数组。

$file[0]为smi1e.php/，也就是reset($file)，然后再令$file[2]为白名单中的jpg。

此时end($file)等于jpg，$file[count($file) - 1]为空。

而 $file_name = reset($file) . '.' . $file[count($file) - 1];，也就是smi1e.php/.，最终move_uploaded_file会忽略掉/.，最终上传smi1e.php。

总结：

以上就是自己的一些笔记和经验，但是，试想一下，如果没有源代码，你又能通过几关呢？

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原文地址：https://www.cnblogs.com/Jleixin/p/12988852.html