漏洞条件：文件可上传——知道文件上传路径——上传文件可以被访问——上传文件可以被执行 文件上传可控点： Content-Length,即上传内容大小 MAX_FILE-SIZE,即上传内容的最大长度 filename,即上传文件名 Content-Type,即上传文件类型 请求包中的乱码字段，即是所上传文件的内容，有可能存在请求包中的可控点还有上传路径
一、漏洞代码
（1）后缀
upload.html <html> <head> <title>文件列表绕过</title> </head> <body> <form action="upload.php" method="post" enctype="multipart/form-data"> <label for="file">Filename:</label> <input type="file" name="file" id="file" /> <br /> <input type="submit" name="submit" value="submit" /> </form> </body> </html> <?php if ($_FILES["file"]["error"] > 0) { echo "Return Code: " . $_FILES["file"]["error"] . "<br />"; } else { $info=pathinfo($_FILES["file"]["name"]); $ext=$info['extension'];//得到文件扩展名 if (strtolower($ext) == "php") { exit("no allow php"); } echo "Upload: " . $_FILES["file"]["name"] . "<br />"; echo "Type: " . $_FILES["file"]["type"] . "<br />"; echo "Size: " . ($_FILES["file"]["size"] / 1024) . " Kb<br />"; echo "Temp file: " . $_FILES["file"]["tmp_name"] . "<br />"; if (file_exists("upload/" . $_FILES["file"]["name"])) { echo $_FILES["file"]["name"] . " already exists. "; } else { move_uploaded_file($_FILES["file"]["tmp_name"], "upload/" . $_FILES["file"]["name"]); echo "Stored in: " . "upload/" . $_FILES["file"]["name"]; } } ?>直接上传php文件：
成功上传：
，
在浏览器访问上传的页面，按说这里apache会解析成php，我这里报了500错误。
查阅资料知道：apache与php的结合方式修改为fastcgi方式，测试会爆500错误，不存在这样的解析漏洞。
http://192.168.189.129:8086/houzhui/upload/1.php.xxxx（实际情况自己判断吧）
（2）js检测上传
<html> <head> <title>JS检查文件后缀</title> </head> <body> <script type="text/javascript"> function selectFile(fnUpload) { var filename = fnUpload.value; var mime = filename.toLowerCase().substr(filename.lastIndexOf(".")); if(mime!=".jpg") { alert("请选择jpg格式的照片上传"); fnUpload.outerHTML=fnUpload.outerHTML; } } </script> <form action="upload.php" method="post" enctype="multipart/form-data"> <label for="file">Filename:</label> <input type="file" name="file" id="file" onchange="selectFile(this)" /> <br /> <input type="submit" name="submit" value="submit" /> </form> </body> </html> <?php if ($_FILES["file"]["error"] > 0) { echo "Return Code: " . $_FILES["file"]["error"] . "<br />"; } else { echo "Upload: " . $_FILES["file"]["name"] . "<br />"; echo "Type: " . $_FILES["file"]["type"] . "<br />"; echo "Size: " . ($_FILES["file"]["size"] / 1024) . " Kb<br />"; echo "Temp file: " . $_FILES["file"]["tmp_name"] . "<br />"; if (file_exists("upload/" . $_FILES["file"]["name"])) { echo $_FILES["file"]["name"] . " already exists. "; } else { move_uploaded_file($_FILES["file"]["tmp_name"], "upload/" . $_FILES["file"]["name"]); echo "Stored in: " . "upload/" . $_FILES["file"]["name"]; } } ?>3、截断（< php5.3.4，且gpc关闭）
<html> <head> <title>0x00绕过</title> </head> <body> <form action="upload7.php" method="post" enctype="multipart/form-data"> <label for="file">Filename:</label> <input type="file" name="file" id="file" /><br /> <label for="file">name:</label> <input type="text" name="jieduan"> <br /> <input type="submit" name="submit" value="submit" /> </form> </body> </html> <?php error_reporting(0); $ext_arr = array('flv','swf','mp3','mp4','3gp','zip','rar','gif','jpg','png','bmp'); $file_ext = substr($_FILES['file']['name'],strrpos($_FILES['file']['name'],".")+1); //exit($_FILES['file']['name']); if(in_array($file_ext,$ext_arr)) { $tempFile = $_FILES['file']['tmp_name']; // 这句话的$_REQUEST['jieduan']造成可以利用截断上传 $targetPath = "upload/".$_REQUEST['jieduan'].rand(10, 99).date("YmdHis").".".$file_ext; if(move_uploaded_file($tempFile,$targetPath)) { echo '上传成功'.'<br>'; echo '路径：'.$targetPath; } else { echo("上传失败"); } } else { echo("不允许的后缀"); } ?>4、文件类型：
<html> <head> <title>Mime Type绕过</title> </head> <body> <form action="upload.php" method="post" enctype="multipart/form-data"> <label for="file">Filename:</label> <input type="file" name="file" id="file" /> <br /> <input type="submit" name="submit" value="submit" /> </form> </body> </html> <?php if ($_FILES["file"]["error"] > 0) { echo "Return Code: " . $_FILES["file"]["error"] . "<br />"; } else { if (($_FILES["file"]["type"] != "image/gif") && ($_FILES["file"]["type"] != "image/jpeg") && ($_FILES["file"]["type"] != "image/pjpeg")){ exit($_FILES["file"]["type"]); exit("不允许的格式"); } echo "Upload: " . $_FILES["file"]["name"] . "<br />"; echo "Type: " . $_FILES["file"]["type"] . "<br />"; echo "Size: " . ($_FILES["file"]["size"] / 1024) . " Kb<br />"; echo "Temp file: " . $_FILES["file"]["tmp_name"] . "<br />"; if (file_exists("upload/" . $_FILES["file"]["name"])) { echo $_FILES["file"]["name"] . " already exists. "; } else { move_uploaded_file($_FILES["file"]["tmp_name"], "upload/" . $_FILES["file"]["name"]); echo "Stored in: " . "upload/" . $_FILES["file"]["name"]; } } ?>5、竞争条件
<html> <head> <title>竞争条件</title> </head> <body> <form action="upload.php" method="post" enctype="multipart/form-data"> <label for="file">Filename:</label> <input type="file" name="file" id="file" /><br /> <br /> <input type="submit" name="submit" value="submit" /> </form> </body> </html> <?php if ($_FILES["file"]["error"] > 0) { echo "Return Code: " . $_FILES["file"]["error"] . "<br />"; } else { echo "Upload: " . $_FILES["file"]["name"] . "<br />"; echo "Type: " . $_FILES["file"]["type"] . "<br />"; echo "Size: " . ($_FILES["file"]["size"] / 1024) . " Kb<br />"; echo "Temp file: " . $_FILES["file"]["tmp_name"] . "<br />"; if (file_exists("upload/" . $_FILES["file"]["name"])) { echo $_FILES["file"]["name"] . " already exists. "; } else { move_uploaded_file($_FILES["file"]["tmp_name"], "upload/" . $_FILES["file"]["name"]); echo "Stored in: " . "upload/" . $_FILES["file"]["name"]; //为了说明，这里直接让程序sleep 10s。 //sleep("10"); //unlink("upload/" . $_FILES["file"]["name"]); } } ?>
