Solved

mysql database hacked: <iframe></iframe> appended to a column

Posted on 2009-07-09
9
510 Views
Last Modified: 2012-05-07
My mysql database was hacked another time. The hacker just append an iframe to the title of my post for each entry. The content in the frame seems to be virus. Could anyone help me to avoid this in the future? I tried to use mysql_real_escape_string() for most of my queries, but not all (maybe I should check all files now). If I use mysql_real_escape_string() to all queries, will I be able to avoid this happening again? Is there any way to avoid hacker write iframe into database? Thanks.
0
Comment
Question by:rxzang
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
  • 2
  • 2
  • +1
9 Comments
 
LVL 78

Expert Comment

by:arnold
ID: 24815025
You should.
Do you directly pass data from your web page into your mysql without validating data content?
It is hard to say.
A way to prevent data corruption in the database is to limit the possibility that an external user can submit queries directly to your database.
 
0
 
LVL 9

Expert Comment

by:wellhole
ID: 24815040
You should convert those < and > characters into the html equivalent before saving it into the database.
0
 

Author Comment

by:rxzang
ID: 24815231
Hi, wellhole:

Do you mean I have to change all my queries?

Thanks.
0
Turn Insights Into Action

You’ve already invested in ITSM tools, chat applications, automation utilities, and more. Fortify these solutions with intelligent communications so you can drive business processes forward.

With xMatters, you'll never miss a beat.

 
LVL 9

Expert Comment

by:wellhole
ID: 24815306
Your queries don't change. You just encode all strings written into the database for user submitted entries.

str = encode(str)

OR

You can encode them when you pull them back from the database. This way you don't have to deal with what people have already entered into your forum.
0
 
LVL 12

Accepted Solution

by:
jet-black earned 500 total points
ID: 24815500
Use the function like that before using your variables in SQL statement:
function prepare_($data, $do_not_use_html=1, $use_trim = 1)
{
    if ($use_trim) { $data = trim($data); }
    if(get_magic_quotes_gpc())
    {
        $data=stripslashes($data);
    }
    else
    {
        $data=addslashes($data);
    }
    $data=mysql_escape_string($data);
    if ($do_not_use_html) { $data = htmlspecialchars($data); }
    return $data;
}
 
example usage:
$data = prepare_($_POST['query']);

Open in new window

0
 

Author Comment

by:rxzang
ID: 24815600
Thanks. I have some function to check mysql data input. But I have a bunch of files, so I didn't use this function everywhere. Maybe I should use this function in all queries I have. Thanks!
0
 
LVL 12

Expert Comment

by:jet-black
ID: 24815635
Also you can also use the function strip_tags to remove all html tags within the field.
http://php.net/manual/en/function.strip-tags.php
0

Featured Post

Free learning courses: Active Directory Deep Dive

Get a firm grasp on your IT environment when you learn Active Directory best practices with Veeam! Watch all, or choose any amount, of this three-part webinar series to improve your skills. From the basics to virtualization and backup, we got you covered.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article shows the steps required to install WordPress on Azure. Web Apps, Mobile Apps, API Apps, or Functions, in Azure all these run in an App Service plan. WordPress is no exception and requires an App Service Plan and Database to install
Microsoft Access is a place to store data within tables and represent this stored data using multiple database objects such as in form of macros, forms, reports, etc. After a MS Access database is created there is need to improve the performance and…
Polish reports in Access so they look terrific. Take yourself to another level. Equations, Back Color, Alternate Back Color. Write easy VBA Code. Tighten space to use less pages. Launch report from a menu, considering criteria only when it is filled…
This is a high-level webinar that covers the history of enterprise open source database use. It addresses both the advantages companies see in using open source database technologies, as well as the fears and reservations they might have. In this…

696 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question