Phorum allows remote attackers to hijack sessions of other users by stealing and replaying the session hash in the phorum_uriauth parameter, as demonstrated using profile.php. NOTE: the affected version was reported to be 4.3.7, but this may be erroneous.
https://exchange.xforce.ibmcloud.com/vulnerabilities/16215
http://securitytracker.com/id?1010219
http://archives.neohapsis.com/archives/fulldisclosure/2004-05/0999.html