Description
WordPress is prone to an SQL injection vulnerability because it fails to sufficiently sanitize user-supplied data before using it in an SQL query. Exploiting this issue could allow an attacker to compromise the application, access or modify data, or exploit latent vulnerabilities in the underlying database. WordPress version 2.3.1 is vulnerable; other versions may also be affected.
Remediation
Update to WordPress version 2.5 or latest
References
http://www.abelcheung.org/advisory/20071210-wordpress-charset.txt
http://www.securityfocus.com/archive/1/484828