Vanilla 'RequestName' Cross-Site Scripting Vulnerability

Summary
The host is running Lussumo Vanilla and is prone to Cross-Site Scripting Vulnerability.
Impact
Successful exploitation could allow remote attackers to execute arbitrary HTML and script code in a user's browser session in context of an affect site and it result XSS attack. Impact Level: Application.
Solution
No solution or patch was made available for at least one year since disclosure of this vulnerability. Likely none will be provided anymore. General solution options are to upgrade to a newer release, disable respective features, remove the product or replace the product by another one.
Insight
Error is due to improper sanitization of user supplied input in the 'RequestName' parameter in '/ajax/updatecheck.php' file.
Affected
Lussumo Vanilla 1.1.7 and prior on all running platform.
References