Lyris ListManager 8.5, and possibly other versions before 8.8, includes sensitive information in the env hidden variable, which allows remote attackers to obtain information such as the installation path by requesting a non-existent page and reading the env variable from the resulting error message page.
http://www.vupen.com/english/advisories/2005/2820
http://www.securityfocus.com/bid/15789
http://www.securityfocus.com/archive/1/419077/100/0/threaded
http://secunia.com/advisories/17943
http://archives.neohapsis.com/archives/fulldisclosure/2005-12/0349.html