Servlet examples in Allaire JRun 2.3.x allow remote attackers to obtain sensitive information, e.g. listing HttpSession ID's via the SessionServlet servlet.
https://exchange.xforce.ibmcloud.com/vulnerabilities/4774
http://www.securityfocus.com/bid/1386
http://www.allaire.com/handlers/index.cfm?ID=16290&Method=Full