WorldClient.dll in Alt-N MDaemon and WorldClient 8.1.3 trusts a Session parameter that contains a randomly generated session ID that is associated with a username, which allows remote attackers to perform actions as other users by guessing or sniffing the random value.

WorldClient webmail in Alt-N MDaemon 8.1.3 allows remote attackers to prevent arbitrary users from accessing their inboxes via script tags in the Subject header of an e-mail message, which prevents the user from being able to access the Inbox folder, possibly due to a cross-site scripting (XSS) vulnerability.

Multiple unspecified vulnerabilities in WorldClient in Alt-N MDaemon before 10.02 have unknown impact and attack vectors, probably related to cross-site scripting (XSS) and WorldClient DLL 10.0.1, a different vulnerability than CVE-2008-6893.