目录
一、htaccess重写解析绕过上传
htaccess文件
htaccess文件可以帮我们实现包括：文件夹密码保护、用户自动重定向、自定义错误页面、改变文件扩展名、封禁特定IP地址的用户、只允许特定IP地址的用户、禁止目录列表，以及使用其他文件作为index文件等一些功能！
htaccess文件上传
如果黑名单过滤了所有的能执行的后缀名，如果允许上传.htaccess。在htaccess文件中写入
SetHandler application/x-httpd-php则可以将文件重写成php文件。PHPstudy中要使htaccess文件的规则生效，则需要在apache开启rewite重写模块，apache大多数都默认开启该模块，所以一般情况下都生效
可以看到我这里是默认开启的
靶场练习pass-04
代码分析
$is_upload = false;$msg = null;if (isset($_POST['submit'])) { if (file_exists($UPLOAD_ADDR)) { $deny_ext = array(".php",".php5",".php4",".php3",".php2","php1",".html",".htm",".phtml",".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, $deny_ext)) { if (move_uploaded_file($_FILES['upload_file']['tmp_name'], $UPLOAD_ADDR . '/' . $_FILES['upload_file']['name'])) { $img_path = $UPLOAD_ADDR . $_FILES['upload_file']['name']; $is_upload = true; } } else { $msg = '此文件不允许上传!'; } } else { $msg = $UPLOAD_ADDR . '文件夹不存在,请手工创建！'; }}可以看到这一关非常丧心病狂啊，直接黑名单了几乎所有的后缀名，而且有很多是我没见过的qwq
创建.htaccess文件
SetHandler application/x-httpd-php 开始上传
上传.htaccess、test.png
上传成功
访问
直接访问一下test.png
成功执行phpinfo()
上传成功！拿webshelll就直接上传一句话木马就ok了
二、大小写绕过
有的黑名单没有对后缀名的大小写进行严格判断（一般不会有），导致可以更改后缀大小写绕过，如PHP、Php、pHp、PhP、pHP....
upload-labs pass-05
代码分析
$is_upload = false;$msg = null;if (isset($_POST['submit'])) { if (file_exists($UPLOAD_ADDR)) { $deny_ext = array(".php",".php5",".php4",".php3",".php2",".html",".htm",".phtml",".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, '.'); $file_ext = str_ireplace('::$DATA', '', $file_ext);//去除字符串::$DATA $file_ext = trim($file_ext); //首尾去空 if (!in_array($file_ext, $deny_ext)) { if (move_uploaded_file($_FILES['upload_file']['tmp_name'], $UPLOAD_ADDR . '/' . $_FILES['upload_file']['name'])) { $img_path = $UPLOAD_ADDR . '/' . $file_name; $is_upload = true; } } else { $msg = '此文件不允许上传'; } } else { $msg = $UPLOAD_ADDR . '文件夹不存在,请手工创建！'; }}仔细看跟上一题的代码有什么区别
$file_ext = strtolower($file_ext); 这句代码是将接收到的文件名都转成小写，然后再与黑名单比对，而这道题显然是没有的
我们可以尝试上传test.PhP
上传
直接上传成功了
访问
成功
三、空格绕过上传
还是黑名单中，如果没对空格进行过滤，可以利用在后缀名中加空格来进行绕过
pass-06
代码分析
$is_upload = false;$msg = null;if (isset($_POST['submit'])) { if (file_exists($UPLOAD_ADDR)) { $deny_ext = array(".php",".php5",".php4",".php3",".php2",".html",".htm",".phtml",".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 if (!in_array($file_ext, $deny_ext)) { if (move_uploaded_file($_FILES['upload_file']['tmp_name'], $UPLOAD_ADDR . '/' . $_FILES['upload_file']['name'])) { $img_path = $UPLOAD_ADDR . '/' . $file_name; $is_upload = true; } } else { $msg = '此文件不允许上传'; } } else { $msg = $UPLOAD_ADDR . '文件夹不存在,请手工创建！'; }}这次少了这一行
$file_ext = trim($file_ext); //首尾去空没有进行首尾去空
尝试上传
这里php后面加了一个空格但是看不出来
尝试上传
感觉像是浏览器自动把空格去掉了，我们抓包，在数据包里加
这里空格就比较明显了，发送数据包
上传成功！
访问
访问成功
四、利用windows系统特征绕过上传
Windows中后缀名.，系统会自动忽略末尾的"."，所以可以通过在末尾加.来进行绕过
到这里我们能发现，前面的代码没有一行是没用的，每一行都针对一种上传方法！
pass-07
代码分析
$is_upload = false;$msg = null;if (isset($_POST['submit'])) { if (file_exists($UPLOAD_ADDR)) { $deny_ext = array(".php",".php5",".php4",".php3",".php2",".html",".htm",".phtml",".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, $deny_ext)) { if (move_uploaded_file($_FILES['upload_file']['tmp_name'], $UPLOAD_ADDR . '/' . $_FILES['upload_file']['name'])) { $img_path = $UPLOAD_ADDR . '/' . $file_name; $is_upload = true; } } else { $msg = '此文件不允许上传'; } } else { $msg = $UPLOAD_ADDR . '文件夹不存在,请手工创建！'; }}这里少了一行去掉末尾的点，看到没
如果少了这一行，正巧传入的参数中末尾有点，经过strrchr的处理后，$file_ext就只有一个点了，跟$deny_ext中任何值都不匹配绕过黑名单
并且下面是使用$.file_name所以不会影响后面的转存
尝试上传
我们在windows中尝试修改后缀名为php.
很遗憾，改不了，因为这个是windows的特性啊，自动忽略
所以我们抓包修改，最后访问test.php就行啦，传到文件夹里这个点就没了
先清空前面传的文件
上传成功，尝试访问test.php
成功
来源地址：https://blog.csdn.net/qq_40345591/article/details/127466181
