V3 Chat allows remote attackers to obtain the installation path via (1) an invalid id parameter to mail/index.php or (2) membername parameter to messenger/online.php, which displays the path in an error page due to an incorrect SQL statement.
https://exchange.xforce.ibmcloud.com/vulnerabilities/27395
http://www.vupen.com/english/advisories/2006/2474
http://www.securityfocus.com/bid/18543
http://www.securityfocus.com/archive/1/438069/100/200/threaded
http://www.securityfocus.com/archive/1/437755/100/200/threaded