source: https://www.securityfocus.com/bid/13560/info

CodeThatShoppingCart is reportedly affected by multiple input validation vulnerabilities. These issues may allow remote attackers to carry out cross-site scripting and SQL injection attacks. An attacker may also potentially disclose sensitive data.

CodeThatShoppingCart 1.3.1 was reported to be vulnerable. Other versions may be affected as well. 

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&id=2"><script>alert(document.cookie)</script>