前言
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文件上传漏洞靶场Upload-labs,在github上下载后部署在win10本地,php版本为5.2.17,测试环境使用Kali虚拟机
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| https://github.com/c0ny1/upload-labs
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Pass-01
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首先尝试上传一句话木马up.php文件发现上传失败,并提示只允许.jpg|.png|.gif类型,但是我们的burp并没有抓到这个包,于是判断此处的限制为前端验证,我们直接查看源代码
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将此处判断文件类型的语句修改,即可正常绕过前端验证
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成功上传后界面出现了刚刚上传的图片,由于上传的是php文件,所以无法正常解析成图片
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右键点击复制图像地址即可得到文件上传的路径,在蚁剑中直接连接
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Pass-02
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先尝试能否直接上传up.php,提示文件类型不正确
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我们在抓到的包中尝试修改Content-Type为image/jpeg,继续上传
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成功上传,复制路径后蚁剑连接
Pass-03
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上传up.php后提示不允许以上后缀,我们尝试后缀改写绕过,将php改写为php5,成功上传,依旧可以被解析为php
(此处与不同环境的apache配置文件有关,配置文件中需要有下面这句话才可以成功)
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| AddType application/x-httpd-php .php .phtml .phps .php5 .pht
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Pass-04
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本题使用以上几种方法均无法上传up.php,黑名单过滤的十分严密,基本只允许上传图片格式,但值得注意的是,黑名单中并没有.htaccess,于是我们可以选择上传.htaccess文件,既然只允许上传jpg文件,我们就上传jpg格式的一句话,再利用我们上传的.htaccess将jpg解析为php,构造如下文件
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再直接上传jpg格式的一句话,并用蚁剑连接
Pass-05
本题相当刁钻,黑名单包括转换,大小写,空格,还有点号,几乎所有php文件都上传不了,并且拒绝上传 .htaccess 文件,源代码如下
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| $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); $file_ext = strrchr($file_name, '.'); $file_ext = strtolower($file_ext); $file_ext = str_ireplace('::$DATA', '', $file_ext); $file_ext = trim($file_ext); 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!'; } }
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黑名单中没有的后缀名有 .php7
以及 .ini
,此处应该使用 .user.ini
解析漏洞,思路和.htaccess
有些相似
使用 .user.ini
解析漏洞需要三个前提条件:
①服务器后端语言为php
②文件上传目录中有可利用的php文件
③服务器使用CGI/FastCGI模式
这个漏洞非常少见,限制条件也很多,感觉实战中并不好用
本关的提示为上传目录存在readme.php,可以利用这个php文件
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我们先上传一个图片格式的一句话木马
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再构造.user.ini
如下,使目录下所有php文件都包含up.jpg,从而将恶意代码注入上传目录中已经存在的可利用php文件中
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根据提示可知,目录下有readme.php,我们输入该文件的地址即可连接
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Pass-06
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直接大小写绕过
Pass-07
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| $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",".ini"); $file_name = $_FILES['upload_file']['name']; $file_name = deldot($file_name); $file_ext = strrchr($file_name, '.'); $file_ext = strtolower($file_ext); $file_ext = str_ireplace('::$DATA', '', $file_ext); if (!in_array($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 { $msg = UPLOAD_PATH . '文件夹不存在,请手工创建!'; } }
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源代码没有去掉空格,直接在文件名末尾加空格绕过黑名单
(Linux不可以,只有在windows下能成功)
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Pass-08
和上一题类似,本题没有去掉文件名末尾的点,故抓包后文件末尾加点绕过
Pass-09
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源代码中没有去掉::$DATA,抓包在文件末尾加上后可绕过检测,但解析时会忽略::$DATA
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Pass-10
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| $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",".ini"); $file_name = trim($_FILES['upload_file']['name']); $file_name = deldot($file_name); $file_ext = strrchr($file_name, '.'); $file_ext = strtolower($file_ext); $file_ext = str_ireplace('::$DATA', '', $file_ext); $file_ext = trim($file_ext); 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!'; } }
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本题源码中能过滤的都过滤了,但可以知道deldot
只会删除末尾的一个点,
故可以构造文件后缀php. .
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Pass-11
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| $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","ini");
$file_name = trim($_FILES['upload_file']['name']); $file_name = str_ireplace($deny_ext,"", $file_name); $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 = UPLOAD_PATH . '文件夹不存在,请手工创建!'; } }
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本题源代码中str_ireplace
会将黑名单中的函数替换为空,故双写绕过
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