source: https://www.securityfocus.com/bid/24210/info

Uebimiau is prone to multiple input-validation vulnerabilities, including cross-site scripting issues and an information-disclosure issue, because the application fails to properly sanitize user-supplied input.

Attackers can exploit these issues to steal cookie-based authentication credentials, to control how the site is rendered to the user, or to gain access to information that could aid in further attacks.

Uebimiau 2.7.2 and 2.7.10 are vulnerable; other versions may also be affected. 

http://www.example.org/demo/pop3/error.php?selected_theme=%3Cscript%3Ealert(document.cookie)%3C/script%3E