The Windows Guest Tools in Citrix XenServer 6.2 SP1 and earlier allows remote attackers to cause a denial of service (guest OS crash) via a crafted Ethernet frame.

Citrix XenServer 4.1, 6.0, 5.6 SP2, 5.6 Feature Pack 1, 5.6 Common Criteria, 5.6, 5.5, 5.0, and 5.0 Update 3 contains a Local Privilege Escalation Vulnerability which could allow local users with access to a guest operating system to gain elevated privileges.

Citrix XenApp Online Plug-in for Windows 12.1 and earlier, and Citrix Receiver for Windows 3.2 and earlier could allow remote attackers to execute arbitrary code by convincing a target to open a specially crafted file from an SMB or WebDAV fileserver.