Description
WordPress is prone to an SQL injection vulnerability because the application fails to properly sanitize user-supplied input before using it in an SQL query. A successful exploit could allow an attacker to compromise the application, access or modify data, or exploit vulnerabilities in the underlying database implementation. WordPress version 2.1.3 is vulnerable; other versions may also be affected.
Remediation
Update to WordPress version 2.2 or latest
References
http://www.waraxe.us/advisory-50.html
http://www.exploit-db.com/exploits/3960/
http://packetstormsecurity.org/files/view/56875/wp213-ajax.txt