asp database help cross scripting problem

Need help removing cross scripting vulnerabilities, and sql injection. Also help developing php site ## Deliverables Vulnerability description This script is possibly vulnerable to Cross Site Scripting (XSS) attacks. Cross site scripting (also referred to as XSS) is a vulnerability that allows an attacker to send malicious code (usually in the form of Javascript) to another user. Because a browser cannot know if the script should be trusted or not, it will execute the script in the user context allowing the attacker to access any cookies or session tokens retained by the browser. Affected items * /catalog/[login to view URL] The impact of this vulnerability Malicious users may inject JavaScript, VBScript, ActiveX, HTML or Flash into a vulnerable application to fool a user in order to gather data from them. An attacker can steal the session cookie and take over the account, impersonating the user. It is also possible to modify the content of the page presented to the user. How to fix this vulnerability Your script should filter metacharacters from user input. Detailed information [][1] ![][2] Click here for more detailed information about this vulnerability