Exposure of Sensitive Information to an Unauthorized Actor
The web portal interface in Citrix Access Gateway (aka Citrix Advanced Access Control) before Advanced Edition 4.5 HF1 places a session ID in the URL, which allows context-dependent attackers to hijack sessions by reading "residual information", including the a referer log, browser history, or browser cache.
CWE-200 - Information Exposure
An information exposure vulnerability is categorized as an information flow (IF) weakness, which can potentially allow unauthorized access to otherwise classified information in the application, such as confidential personal information (demographics, financials, health records, etc.), business secrets, and the application's internal environment.