The USB redirection feature of Citrix XenDesktop allows a user to redirect USB devices on the client to their XenDesktop Virtual Desktop Agent (VDA).
A weakness has been identified in the Citrix XenDesktop VDA implementation of USB redirection that could result in changes to the server-side policy controlling USB redirection not being propagated to the VDA. This could allow an authenticated user to gain access to their USB devices in contravention of the updated administrator-defined policy.
This issue affects all versions of Citrix XenDesktop Virtual Desktop Agent 5.x, up to and including version 5.6.
This vulnerability has been assigned the following CVE number:
Only customers that have modified server-side policy to disable USB redirection are affected by this weakness.
What Customers Should Do
A new version of the VDA has been released to address this issue. Citrix recommends that affected customers upgrade to this version of the VDA, which can be downloaded from the following locations.