For those of you that use Citrix....
http://www.frsirt.com/english/advisories/2006/3643
A vulnerability has been identified in Citrix Access Gateway, which could be exploited by attackers to bypass security restrictions. This flaw is due to an error in the Advanced Access Control option (AAC) when configured to use LDAP authentication, which could be exploited by attackers to gain unauthorized access to a vulnerable application without supplying valid credentials.
Affected version: Citrix Access Gateway with Advanced Access Control version 4.2
Note: None of the Citrix links are working at time of publication.