source: http://www.securityfocus.com/bid/9997/info

Reportedly A-Cart is prone to multiple input validation vulnerabilities. These issues are due to a failure of the application to properly sanitize user supplied input prior to its use in SQL queries and generation of dynamic content.

The SQL injection issue may allow a remote attacker to manipulate SQL query logic, potentially leading to access to sensitive information such as the administrator password hash or corruption of database data. SQL injection attacks may also potentially be used to exploit latent vulnerabilities in the underlying database implementation.

The cross-site scripting issue could permit a remote attacker to create a malicious link to the vulnerable application that includes hostile HTML and script code. If this link were followed, the hostile code may be rendered in the web browser of the victim user. This would occur in the security context of the affected web site and may allow for theft of cookie-based authentication credentials or other attacks. 

http://www.example.com/category.asp?catcode=[SqlInjection]
http://www.example.com/category.asp?catcode=1%20union%20all%20select%20pass,0,0,0,0%20from%20customers%20where%20fname='[Username]' 