source: https://www.securityfocus.com/bid/17974/info
 
PSY Auction is prone to multiple input-validation vulnerabilities. The issues include HTML-injection and SQL-injection vulnerabilities. These issues are due to a failure in the application to properly sanitize user-supplied input. 
 
Successful exploits of these vulnerabilities could allow an attacker to compromise the application, access or modify data, steal cookie-based authentication credentials, control how the site is rendered to the user, or exploit vulnerabilities in the underlying database implementation. Other attacks are also possible.
 
http://www.example.com/auction/email_request.php?user_id=[malicious code]