Some vulnerabilities have been reported in WordPress, which can be exploited by malicious users to conduct script insertion attacks and bypass certain security restrictions, and by malicious people to conduct SQL injection attacks.

1) The "unfiltered_html" privilege feature can be bypassed by adding a field named "no_filter". This can be exploited by malicious users without the "unfiltered_html" privilege to e.g. post blog entries with arbitrary HTML and script code via specially crafted POST requests.

2) Input passed to certain parameters (e.g. the "post_type" parameter of the URL passed to the "pingback.extensions.getPingbacks()" XMLRPC method) is not properly sanitised before being used in SQL queries. This can be exploited to manipulate SQL queries by injecting arbitrary SQL code.

3) A vulnerability is caused due to improper access restriction. This can be exploited to bypass the authentication mechanism and e.g. switch themes or activate/deactivate plugins without valid administrator credentials, by passing malicious data in the "PATH_INFO" part of a URL.

Successful exploitation of this vulnerability requires valid user credentials.

The vulnerabilities are reported in Wordpress prior to 2.2.3 and Wordpress MU prior to 1.2.5a.

Solution
Update to Wordpress version 2.2.3 or Wordpress MU version 1.2.5a.

Provided and/or discovered by
1) xknown
2) Alexander Concha, buayacorp.com
3) xknown

Changelog
Further details available to Secunia VIM customers

Original Advisory
1) http://trac.wordpress.org/ticket/4720
2) http://www.buayacorp.com/files/wordpress/wordpress-sql-injection-advisory.html
3) http://trac.wordpress.org/ticket/4748

Deep Links
Links available to Secunia VIM customers