source: https://www.securityfocus.com/bid/16020/info
 
Papoo is prone to multiple SQL-injection vulnerabilities. These issues are due to a failure in the application to properly sanitize user-supplied input before using it in SQL queries.
 
Successful exploitation could allow an attacker to compromise the application, access or modify data, or exploit vulnerabilities in the underlying database implementation.
 
These issues affect version 2.1.2; other versions may also be vulnerable. 

http://www.example.com/guestbook.php?menuid=[SQL]