source: https://www.securityfocus.com/bid/17967/info

Gphotos is prone to multiple input-validation vulnerabilities. The issues include information-disclosure and cross-site scripting vulnerabilities. These issues are due to a failure in the application to properly sanitize user-supplied input. 

A successful exploit of these vulnerabilities could allow an attacker to compromise the application, access or modify data, or steal cookie-based authentication credentials. Other attacks are also possible.

http://www.example.com/index.php?rep=[xss]