在注册的时候,输入用户名后台会验证用户名是否存在,当然是通过ajax去验证的也就是ajax.php。很多程序多会忽略这个导致存在SQL注入。
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* 验证会员数据 */ function check_user($field_name,$field_data) { //开始数据验证 $user_data[$field_name] = $field_data; $res = array('status'=>1,'info'=>'','data'=>''); //用于返回的数据 if(trim($user_data['user_name'])==''&&$field_name=='user_name') { $field_item['field_name'] = 'user_name'; $field_item['error'] = EMPTY_ERROR; $res['status'] = 0; $res['data'] = $field_item; return $res; } if($field_name=='user_name'&&$GLOBALS['db']->getOne("select count(*) from ".DB_PREFIX."user where user_name = '".trim($user_data['user_name'])."' and id <> ".intval($user_data['id']))>0)//这里的$user_data['user_name']的值就是用户名提交过来的值,这里只是过滤了空格。所有存在SQL注入漏洞。 { $field_item['field_name'] = 'user_name'; $field_item['error'] = EXIST_ERROR; $res['status'] = 0; $res['data'] = $field_item; return $res; }
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