Andy's PHP Knowledgebase Multiple Cross-Site Scripting Vulnerabilities

This host is running Andy's PHP Knowledgebase and is prone to multiple cross site scripting vulnerabilities.
Successful exploitation will allow attacker to insert arbitrary HTML and script code, which will be executed in a user's browser session in the context of an affected site. Impact Level: Application
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.
The flaws are caused by improper validation of user-supplied input passed via the 'username' parameter in login.php and forgot_password.php, 'first_name', 'last_name', 'email', 'username' parameters in register.php, and 'keyword_list' parameter in keysearch.php, that allows attackers to execute arbitrary HTML and script code on the web server.
Andy's PHP Knowledgebase version 0.95.5 and prior.