Re: Simple Machines Forum (SMF) XSS issue
I wouldn't rely on that library by itself. As I emailed Kallahar quite
a while ago about it is still vulnerable to at least one issue:
<IMG
SRC=ja&#x09;vascrip&#x09;t:alert(String.fromCharCode(88,83,83));>
This works in IE6.0 and Opera 9.0. What it is doing is converting HTML
entities into their ASCII equivalent. By doing that he is changing my
string, "&#x09;" into "	" which is a newline, and injected
within the javascript directive it breaks it up. This is a pretty good
example of why conversion filters can be used against you.
-RSnake
http://ha.ckers.org/
http://sla.ckers.org/
On Sat, 21 Oct 2006, mrapples@xxxxxxxxx wrote:
Good find on this.
Here is the fix I applied:
Find on line ~85 in Sources/Search.php:
foreach ($temp_params as $i => $data)
{
@list ($k, $v) = explode('|\'|', $data);
$context['search_params'][$k] = stripslashes($v);
}
Change to:
foreach ($temp_params as $i => $data)
{
@list ($k, $v) = explode('|\'|', $data);
$context['search_params'][$k] = RemoveXSS(stripslashes($v));
}
The RemoveXSS function is taken from the following site:
http://quickwired.com/kallahar/smallprojects/php_xss_filter_function.php
I hope that handles all the issue related to this.