source: https://www.securityfocus.com/bid/22697/info

Shop Kit Plus is prone to a local file-include vulnerability because it fails to adequately sanitize user-supplied data.

An attacker can exploit this vulnerability using directory-traversal strings to execute local script code in the context of the application. This may allow the attacker to access sensitive information that may aid in further attacks.

http://www.example.com/shopkitplus/enc/stylecss.php?changetheme=../../../../../../../../../../../../etc/passwd