php项目ueditor上传pdf文件,防止XSS攻击
做渗透测试的时候,ueditor附件上传一个包含javascript代码的pdf文件,直接保存成功。
通过浏览器访问这个保存好的文件,会执行javascript代码。被评定为高危漏洞。
项目使用的ueditor1.4.*,发现ueditor只做了文件大小和后缀的验证,没有做内容是否包含javascript代码的验证。
思路是在ueditor处理文件上传成临时文件验证的地方(移动之前),加上验证,不通过就直接返回,跳过文件移动。
修改ueditor包含的Uploader.class.php文件可以实现
1、添加ERROR_XSS错误提示,只加末尾那一行
private $stateMap = array( //上传状态映射表,国际化用户需考虑此处数据的国际化"SUCCESS", //上传成功标记,在UEditor中内不可改变,否则flash判断会出错"文件大小超出 upload_max_filesize 限制","文件大小超出 MAX_FILE_SIZE 限制","文件未被完整上传","没有文件被上传","上传文件为空","ERROR_TMP_FILE" => "临时文件错误","ERROR_TMP_FILE_NOT_FOUND" => "找不到临时文件","ERROR_SIZE_EXCEED" => "文件大小超出网站限制","ERROR_TYPE_NOT_ALLOWED" => "文件类型不允许","ERROR_CREATE_DIR" => "目录创建失败","ERROR_DIR_NOT_WRITEABLE" => "目录没有写权限","ERROR_FILE_MOVE" => "文件保存时出错","ERROR_FILE_NOT_FOUND" => "找不到上传文件","ERROR_WRITE_CONTENT" => "写入文件内容错误","ERROR_UNKNOWN" => "未知错误","ERROR_DEAD_LINK" => "链接不可用","ERROR_HTTP_LINK" => "链接不是http链接","ERROR_HTTP_CONTENTTYPE" => "链接contentType不正确","ERROR_XSS" => "文件内容包含代码",);2、添加一个验证方法,建议加在 private function checkSize()方法后面:
/*** 文件内容检测* @return bool*/private function checkXSS($tmp_file){$text = file_get_contents($tmp_file);$text = str_replace(array("\r\n","\r","\n"), " ", $text);preg_match('/javascript/i', $text, $matches);if($matches){return false;}return true;}3、upFile方法开头调用这个checkXSS方法验证
private function upFile(){$file = $this->file = $_FILES[$this->fileField];if (!$file) {$this->stateInfo = $this->getStateInfo("ERROR_FILE_NOT_FOUND");return;}if ($this->file['error']) {$this->stateInfo = $this->getStateInfo($file['error']);return;} else if (!file_exists($file['tmp_name'])) {$this->stateInfo = $this->getStateInfo("ERROR_TMP_FILE_NOT_FOUND");return;} else if (!is_uploaded_file($file['tmp_name'])) {$this->stateInfo = $this->getStateInfo("ERROR_TMPFILE");return;} else if (!$this->checkXSS($file['tmp_name'])) { //检查是否包含javascript代码$this->stateInfo = $this->getStateInfo("ERROR_XSS");return;}
// 加了上面末尾三行