source: http://www.securityfocus.com/bid/16260/info
 
Apache Geronimo is prone to multiple input-validation vulnerabilities because the application fails to properly sanitize user-supplied input.
 
A successful exploit could allow an attacker to compromise the application, access or modify data, or steal cookie-based authentication credentials. The attacker could also exploit this issue to control how the site is rendered to the user; other attacks are also possible. 

http://www.example.com/script-that-dont-has-to-exist.jsp?foobar="/><script>alert(document.cookie)</script>